Of course everyone is actually there to meet people, but you can't look like that's what you're doing. You have to look like you're doing something else, to lower the stakes of the interactions. Everyone has to look like they're not trying.
Having some other activity involved (having a drink or otherwise) lowers the stakes when interacting with new people.
Most of human interactions is a facade of some sort. Smalltalk, icebreakers, most of early dating, even most professional conversations.
I know introverts and folks on the spectrum find this intolerable. But it's the foundations of human society.
You can hate it, but hating it will only make you angry. Instead, treat it like a game. There are many games you can play in the world to deal with something painful or frustrating.
If you're stuck trying to fall asleep, you pretend you're counting sheep jumping a fence.
If you're stuck in traffic, you try to guess which lane might be moving faster and make micro optimizations to get their faster.
If you're stuck looking for a life partner in a social setting, the game is act like you don't need one, that your life is fully complete without them, and that you don't care about any one specific given social interaction. Of course, the best way to play that game is to actually live that authentic life. But we all fail at hiding our emotions and true intentions in one way or another. So we play games to camouflage it like holding a drink and acting like that's all that we need to be engaged and interested.