Do you know what is even worse than a touchy subject like cat declawing that suddenly turns everyone around you into the Hulk? A touchy subject that turns everyone around you into Dear Abby.
Try mentioning any of the below things to a large group of people -- or just try not hiding any of these things from a large group of people -- and you will have so much condescending advice on your hands that you could, I don't know, build a really annoying house out of it. You'll be surprised at how many people you like and respect will suddenly turn into advice columnists from hell.
Just mention you are trying to lose a few pounds, and you will be inundated with Diet Experts. Some of them may understand the science, and some of them may have lost weight themselves, and sometimes both, but you can probably bet on neither.
"Look, here's what you need to do."
People who can't keep a pound off will be telling you to stay off carbs and eat all meats, and others will be telling you to banish meats and stick to carbs. Or that if you eat all bananas in the morning, you can eat whatever you want the rest of the day. Some people will tell you it's all about how often you eat, and other people will say it's all about eating nothing after 7pm (a sort of elderly Gremlin diet).
"Midnight? I can't even stay up past 8 anymore."
Whatever they tell you, they will insist that this is the only right way, that this is THE weight loss secret. It doesn't matter what else you eat, as long as you get that morning banana. Or you stay off carbs. Or whatever. If you don't want to listen, they'll throw up their hands and encouragingly tell you that you're doomed to failure.
Morning Banana would be a good name for a band.
This advice actually comes less from a certainty that whatever they're suggesting will work, than from a certainty that whatever you're doing won't work. About half of all Americans are trying to lose weight at any given time, so any given person is likely to have tried a bunch of different methods, which apparently don't work, otherwise they wouldn't keep trying. It takes an incredible amount of discipline to actually lose weight and keep it off, and most people have trouble accepting how much work they'd have to put in, so when they fail, they blame the method and move on to a new one.
Like the Taco Bell diet. Reasoning: It tastes terrible, so it must be good for you!
Because it can't be because weight loss is really hard. It must be because they just haven't found the right diet yet. This next one must be the right one! And if you, their poor sap of a friend, are trying one of the methods they've already tried and failed at, you're clearly barking up the wrong tree, and they've got to stop you for your own sake.
"Stay off the court, Rick, you are just wasting your time with cardio."
I'd suggest you not tell anyone when you're trying to lose weight, but it's pretty hard to get anywhere when your friends unknowingly take you out to Cheesecake Factory or have you over for backyard BBQs, so you have to tell someone. If anyone gives you trouble, you can just tell them you're on the Facepunch Diet, where you punch someone in the face every time they give you diet advice, and that you have never burned so many calories in your life.
Even if you're not a parent, don't know any parents, and haven't been near a child since the brief period where you were one, you've probably heard someone complain about unsolicited parenting advice. If not, here's one parent's experience, to catch you up:
"Why would you deny your precious infant breast milk?" said to a friend who had just adopted. Or, my favorite, offered to a weary mother entertaining two kids during an airport delay: "This is coming from a place of love. That's really not a developmentally appropriate task for your daughter."
This, on the other hand, is.
Another stranger told a mom her baby would claw his face off if she didn't cut his nails.
"I can't let them identify me."
Why does everyone want to tell parents what to do, even people with no kids?
Well, parenting is pretty much the most important responsibility most people will ever have -- you have an entire person's life in your hands. So, many parents, especially first-timers, tend to panic about everything, like whether they started their child listening to Baby Mozart six months too late for the maximum developmental boost, or whether their infant's lack of interest in NFL telecasts indicates they might be gay (or European).
Minor choices, or things that differ from kid to kid, can take on catastrophic significance, and people can project this sense of urgency onto other parents, leading them to assume that the proper timeline of Baby Mozart exposure is as much of a life-and-death issue to others as it was to them when they first found out.
Just so you know I'm not making this up.
So they don't see it as annoying a stranger over a minor problem like having crumbs on their lip, they see it as warning someone that's about to step off a cliff.
As for non-parents, a lot of it is Monday-morning quarterbacking, where things look easier and more obvious when you don't have to actually do them. And when it comes to people offering advice about shutting up a crying kid in public, well, that's because the average human mind isn't equipped to come to terms with a world where turning off that awful sound is not possible. There must be a method. If there is a loving God in heaven, there must be.
Go to your average general forum/newsgroup/mailing list and look for a discussion asking about problems with any Windows machine. Odds are good that somewhere in there, you will find someone suggesting they should have gotten a Mac.
They will do anything to convince you.
Ask about any problem with any Windows machine, and you can almost bet on getting this response:
Even money that their sig contains a quote from Steve Jobs or some kind of smug zing at Bill Gates or Dell or whatever.
Here's how the rest of the thread will play out: 4 helpful suggestions, 2 more "you should have got a Mac" comments, 3 suggestions that end by pointing out this would never happen on a Mac, and 1 guy promoting Linux.
Probably this guy.
Likewise you have this response to "How long will Windows take to install?", or this question about getting a black screen in Windows Media Center, this question about a blank screen in general, a thread about what camera to buy, or this question about popup ad problems.
Not to pin this whole phenomenon on annoying Mac fanboys alone. You'll see the same thing play out if you ask a broad group about what gaming console to get. The Playstation vs. Xbox assholes are a sight worse than Mac assholes, and I only don't quote them here because I can't read most of their misspelled leetspeak posts.