Generally speaking, there are three qualities that turn a situation into a pissing contest. Don’t take this too seriously, but here are the three that come to mind:
Identity. The situation must involve the self-image of the participants.
Competition. The situation must involve some way of comparing oneself to others.
Subjectivity. Those aspects of oneself that can be compared to others must be in some way arguable, or less than objective.
If the above sounds a little vague, that’s because I’m trying to capture a really broad range of phenomena. Basically, this characterizes what sorts of things a person can be a snob about: music, movies, food, drugs, wine, craft beer, cigars, video games, PC parts, guitars, cars, cheese, sports, what have you.
Music, for example. People’s identity is tied up in what they listen to; you can compare your taste against that of other people and get pissy when it’s not exactly the same as yours; whether or not one piece of music is better than another is highly subjective. And this is why, half way through my college years, I made a “rule” that I would not be friends with anyone who attended indie shows. I swear, there is nothing more insufferable than someone who wants to constantly start a cat fight with you over shitty indie bands: “Yeah, early Xiu Xiu is okay, but why do you have their latest album?” This kind of crap is why I threw out most of my music collection and spent a few years listening exclusively to classical music. Then I ran into the people who think tonality is passe and can’t stand listening to anything composed before 1915. Back at square one.
Weed is another illustrative example, because it shows that pissing contests are nested in an almost fractal manner. Not only can you dick-wave about your hobby, but you can also dick-wave about all the various sub-fields of your hobby. I became acquainted with this one back in my teens/20s when I was smoking tons of grass. Go onto any pot forum online and you’ll see stuff like this:
A: “See all this dope-ass glassware on this kitchen table? I’m an unemployed 18 year old and this is all mine. How does that make you feel?”
B: “You pussy. Why do all of your pieces have ice pinches? Do you need someone to hold your hand while you inhale? LOL”
A: “Yeah, whatever. I take one hit off of one of these and I can’t find my keys for hours.”
B: “Can’t find your keys? Sounds like you can’t handle your shit.”
Round and round. Not only are they snobs about what specific strain of dope they’re smoking (complete with dick-sizing statistics about THC content and alkaloid chemistry), but they even get after each other about what instruments they’re using to smoke their dope. And if both of them prefer upright glass bongs with carbs and diffusers but no ice pinch, then they’ll start a catfight over whether or not a bong should have one diffuser or two. I’m serious. I’ve seen it.
But really, it shouldn’t surprise you. Weed fits all three of my criteria: being a stoner is a lifestyle (thus part of one’s identity), it allows for comparison (of strain and paraphernalia, among other things), and it’s totally subjective as to what dope and what instruments you prefer. Predictably, it becomes a pissing contest.
Another example of the fractal nesting I mentioned earlier is guitars. See, when guitar snobs argue, they almost never mention actual music. They never accuse one another of being poor players or of not having good musical taste. No, the ownership of the physical instrument is its own vast subculture, replete with its own special brand of self-aggrandizement and preening. And it’s never over anything significant, like digital amps vs. tube amps. No, we’re talking about enraged, forehead-vein-popping arguments over whether 1960s alnico humbucker is a more authentic choice than one from the 70s. Maybe I’m just being spiteful, but I have to wonder if these people would be able to tell the difference while blindfolded and listening to the guitar being played. Then again, I also have to wonder if any of them can even play the damned instrument. Maybe they just collect guitars to hang them on walls and beat off to them: “Mmmm, vintage 60s electronics with an authentic Floyd Rose… Oh fuck…”
But, again: being guitarist can be a religion for some people. It’s who they are. Different people own different guitars and there are plenty of gear specs as to which guitar is better than another. And the difference in the ever-mysterious “tone” is not only debatable, but scarcely even detectable by the uninitiated.
One observation I’ve made on a lot of answers is that most of us never really grow up. Our behavior as adults is the same as our childhood behavior, only more subtle. The kinds of absurd posturing you see between high school kids doesn’t stop when we get out of high school, not for most people. If you’re not one of those rare genuinely mature people, then you’re probably gonna just find an excuse to do the same thing as an adult, in a more subtle way. And making snippy comments about someone else’s taste in vintage 40s pipe tobacco on an internet forum is one more way to do that.