Assuming that expressions of cultural incomprehension fall under the 'et cetera' component of this blog's purview, let me ask: why do people like to meet in commercial places (coffee shops, bars, etc.)? It seems to me like a double cost: firstly, the environment is intrinsically less pleasant than elsewhere (cf. a comfy private lounge, or stroll through the park), and then - to add insult to injury - one is expected to waste money on consumables whether one really wants them or not.
Maybe the idea is that most people really like the consumables. That'd be fine, I'd happily endure a cramped and noisy coffee shop for the sake of a caffeine-craving friend. My worry is just that there seems to be a social norm that people should meet in such places, and so a group of people might end up meeting there merely due to the norm and not because anyone actually prefers this location over non-commercial alternatives. "Meeting for coffee" is the expected behaviour. I'd rather invite people for a stroll in the park, but they might think that weird. Depending on my mood, that may or may not bother me, but it seems like the sort of thing that would deter many people from socializing in a way that they'd actually enjoy more. (Whether there really are "many people" who share my idiosyncratic tastes here is, of course, another question!)