In California, I work most days at my house up in the Santa Cruz mountains. The round trip to the valley is an hour (assuming zero traffic). So meeting with someone is never just a matter of "grabbing coffee;" it consumes a big chunk of an afternoon. And an interruption on that scale means I will get significantly less programming or writing done that day. I solve the problem of meeting with YC founders who need to talk to me by designating blocks of time as office hours at YC several times a week. But this wouldn't work well for meeting other people. Among other things, there's not much privacy; YC is effectively one giant room. I'm still willing to meet in person with people who feel they need to talk to me about something very important. But if it's possible to talk via phone or email, that would be a lot easier for me.