No, it's unacceptable. When people are not at work, they should be thinking about work, planning for it, and hell, still doing it, only unpaid.
I say we shouldn't even have a distinction between work and home. We should set up dorms so that people don't have to leave the premises. Rent can just be taken out of their pay, talk about convenience! In fact, do they really need to get paid, when the company can provide all their needs? Isn't getting to do the work reward enough?