I don't care if you stand in line for beer. It's your time on this planet, and you can choose to spend it pretty much any way you want. Liberty, you know?
This is one of those things, though, that lots of people seem to like to weigh in on, criticize, laud, judge, defend, or justify. I'm not interested in taking sides here, but that doesn't mean I don't have anything to say on the question. What I'd like to do is draw a distinction between two different kinds of beer-waiting (at the brewery and at a beer festival) and suggest a general approach.
Staking Out the Brewery
I know some who do this, and if you're that committed, go for it. I don't, but I also wouldn't wait in line for Super Bowl tickets even though I'm a big football fan: I have a less-challenging option (watching at home) that gives me about as much utility for a lot less cost and a lot more convenience. Same thing with beer. I might not get that super-rare bottle of whatever, but I can get something that's probably really close to it (or better, if I'm lucky) without the wait.
If you are going to wait in line for beer at a brewery, I have to say that in my mind the only kind of beer that it makes sense for is for an especially hop-driven beer that needs to be consumed right away. In that one instance, you're presumably getting it as fresh as can be, which matters if we're talking something with hop character as a defining attribute. So get your bottle(s), cool to serving temperature, and enjoy! That seems rational to me.
But as I said, if you're just a devotee of a particular brewery, or really like the novelty of limited-release beers, or just want to show up your not-as-committed beer friends, then that's an end in and of itself. Set up your folding chair and enjoy.
The Beer Festival Queue
This is the much more fluid and fascinating scenario: what's your general approach to lines at a beer festival?
I'm an "opportunity taster" at the beer fest. I don't wait in line for anything. I'll be there for a couple of hours, and I almost certainly won't get to every booth no matter what I do, so I'm looking to maximize the number of different breweries I can "touch" in the time I have, since I look at these things as a way to test-drive breweries I haven't experienced or check back in with some I have experienced but just didn't like that much.*** If I'm waiting in line at Brewery A, I'm missing my chance to hit Breweries X, Y, and Z in that same span of time. I know that this could mean that I'm self-selecting my way into less-popular beers or breweries (since maybe there's no line there because their stuff sucks), but I'm happy to balance that risk against the counterbalancing likelihood that these breweries aren't bad as much as they are unknown, and thus don't draw a crowd.
Which doesn't mean it's irrational to wait at the festival. It makes sense to me to wait in line if you're at/from a place that doesn't get a big selection of highly-regarded or popular beers. We're spoiled here in/around Philadelphia because we get damned near everything (hell, during Philly Beer Week you can get two-dollar six-ounce pours of Dogfish 120 and World Wide Stout, Pliny the Elder and Blind Pig, etc.). But if you're from Nebraska and don't see as much of this stuff and you see a booth that's offering something you might not get access to, then it makes all the sense in the world to wait for it.
It also makes sense if, like my wife, you have very specific tastes in your beer/alcohol products. At the Opening Tap Beer Festival at last year's National Homebrewers Conference, Barbara basically just camped out in the Moonlight Meadery line to get a steady-but-small supply of their braggot. Hell, in that case I was grateful for the line - if it wasn't there, she'd have likely been hammered by the end of the night...
Though, as I said, it's your time and your glass. Do what you want. Heck, if you're a line-waiter, you're actually helping us non-waiters, creating a symbiotic and helpful beer fest ecology.
Let It Go
[You're hearing the song in your head now, aren't you?] In any case, though, maybe don't spend time thinking about this or expounding upon it, either to express your disbelief ("Why would anyone wait hours for a just-OK DIPA?") or disparage the action itself. And if you're a "waiter," maybe don't take umbrage when your "Been in line since last night!" social media post isn't an immediate hit.
There's lots of beer out there, and lots of ways to get it, and lots of ways to approach it. My advice isn't to wait, or not - it's to make a choice and take a deliberate approach to it. Make a decision about what and how you want out of beer, and then do what flows logically from that.
Keep it simple.
***And no, this doesn't make me a hypocrite. I know that only two weeks ago I argued against the idea of judging beers based on a 2-ish ounce pour of them, but at a festival I don't have any other option. Requesting a full pour would result in a "Sideways"-esque scene, and/or endangering someone's liquor license or insurance. But I'd note here that I don't make determinations at festivals - it's just data for the computer, and I'd never write off a brewery or even a single beer based on that one pour at the fest!