Personally, at that point I would start demanding 24/7 pay coverage. You don't get to tell me what I can or cannot do outside of the hours that you're paying for.
They probably believe people should feel honored to work for them for free, but paying you less than fair market salary and taking away all your hobbies is the most they can get.
This is usually a problem for lower paid jobs, not for developers.
Hiring a good developer is hard, hiring a good cleaner is simple.