If he don't want to act on Sunday, that's his choice, but that's not to say that theater should be closed on Sunday.
If he wants to take Sunday off, all well and good.
If they want a production of Hairspray on Sundays then give it to the understudy.
Hell, give the understudy a couple of nights a week and spread the wealth a little (both cash and experience, the later being the more lucrative IMHO).
Saying theater should be closed because you don't want to work that day is going a little far
