People on my broader distributed team accept that periodic multi-day weekday off-sites are part of the deal. Can't really avoid some weeknights traveling. But, then, all of us normally do a lot of business travel anyway. Periodic F2F is important and there's no way to do it just on company time if everyone isn't in the same location. If someone really can't, they can dial in but that's inevitably not a great experience when everyone else is in the same room.
It's probably on a manager by manager basis. If I work a weekend day on business--whether because of travel or because there's a software community event on the weekend--I can take a comp day. For nights not really. But if I get home late at night, no one's going to bat an eye if I take it easy in the morning so long as there's nothing I have to do. My time is usually pretty flexible.
