Coffee shops that wish to encourage socialization can provide large tables which seat 6-12 rather than two-tops.
I was a regular at a coffee shop for 7 years, and this was one of the reasons. (RIP Rebecca's Coffee House.) I met lots of people by striking up conversations with someone seated at the same large table.
(Some people don't want to talk, but if you have the social skills to read the signs, it's no big deal.)
Even without such a rule, it's still a social win over 5 two-tops with one patron each, as far as I'm concerned — and it's probably a wash for per-square-foot revenue.
I was a regular at a coffee shop for 7 years, and this was one of the reasons. (RIP Rebecca's Coffee House.) I met lots of people by striking up conversations with someone seated at the same large table.
(Some people don't want to talk, but if you have the social skills to read the signs, it's no big deal.)