This isn't innuendo for anything.
I have a really bad habit of staring off into space. Do this in a room full of naked guys and it seems like your glassy-eyed, slack-jawed expression has been brought on by an overwhelming sense of wiener admiration, and not every man is comfortable with that. Now you're forced to try to explain that you weren't staring at his junk, it's just that his junk ended up in your frame of view, and you were absently staring at a wall, thinking about blueberry cheesecake lube or whatever. There's no subtle way out of it, and it's so much worse than when you were a kid and could blame it on being sugar-addled or just stupid. Plus it means you need to go to a new gym now, and one day you'll run out of new ones.
The real issue here is the way our culture reacts to staring. How many times have you heard "Don't stare!" when you were growing up, or been made uncomfortable by someone else staring at you? Ever wonder why? Looking at people is not wrong, but it can be creepy to us. A woman wears a super low-cut top, you stare at her boobs, you're being a creep. I say fuck that. If I can see a thing when I'm out and about shopping for bagels and spray cheese, it's not my fault if I look at it. Don't tell me what to do with my eyes. And likewise, if you're insisting that I have to wash my dick in a room full of other dicks because somehow that is culturally normal, don't tell me it's not normal to see another dick. I'm going to look at every dick and tit that crosses my field of vision from now on, no matter how awkward it makes the dinner party.