The reality is actually more interesting. Those Stormtroopers, like our source Brian, are part of the 501st Legion, a fan-run costuming conglomerate that Lucasfilm rings up whenever they need to produce an imperial butt-ton of walking, talking Star Wars villains. Mentions of the 501st Legion in Star Wars media such as the Clone Wars TV series are actually a "wink wink, nudge nudge" to the organization, which was created under that name in 1997 and today has over 8,000 active members in more than 100 "garrisons," from Alabama to Slovakia.
And, keep in mind, each of those people has likely poured thousands of dollars into their costumes. "At the high end," says Brian, "you have costumes such as Boba Fett and Darth Vader, which can run upwards of $5,000, are very complex, and which sometimes take years to locate the correct parts." What, you thought you could rent film-quality gear from a costume shop? Oh, no -- if you're joining the Legion, you're taking on a part-time job that will consume a significant part of your life.
Part of the hassle is that, since the organization isn't officially part of Lucasfilm or Disney, they operate under a sort of "don't ask, don't tell" policy by restricting all of the buying and selling of armor kits to members-only boards -- selling the stuff openly would be a trademark violation. Somewhere in your neighborhood there might be a guy with a full-blown old-school Hollywood prop-making studio in his garage, but he can't go around advertising the fact for fear of Lucasfilm dispatching an Order 66 via copyright lawyers. "While sculpting your own molds and building your own vacuum-forming apparatus is an option for those who have the time and talent to do so, the vast majority of people purchase kits from a handful of well-known vendors who have already made the large investment (typically tens of thousands of dollars and hundreds of labor hours) in setting up the infrastructure."
If thousands for a costume seems like a lot to explain to a skeptical spouse,
try justifying an injection molder.