That's a huge reason why most people don't stick with uberman. Even uberman, once adapted, allows for 3.5h wake times.

Everyman, though, allows one to be quite functional with just a few naps earlier in the day. My current schedule (core 0030-400, naps 0730, 1130, ~330) has the first nap around the time other people are getting up anyway, and then the second during lunch, then the third is fairly flexible, and I have it whenever in the afternoon makes sense. I'm a student; my lunch is the same time every day, but sometimes I have to push back the afternoon nap or skip half a lecture to take it. At any rate, I'm totally free during evening/social hours, aside from not being able to stay out late. It appears, though, that periodically one can do an earlier core then stay out, or do a late one, and this is not so bad.

When I was interning at a tech startup, I would just nap as I needed/wanted. Based on another recent round of interviews, it seems that about a third of tech companies are supportive, a third supportive, and a sixth each reluctant and completely disapproving. Small companies tend to be in the more pro-nap groups, larger companies vary widely. (I didn't keep actual stats on this, so the fractions are rough. The number of companies I asked was <10.)