Is it OK for degree mills to give certificates?

Yes, you can get a license that work and do things. Why pay $7000 for degree when you can get a church one for $100 the most? It has to be more than getting a piece of paper. Personally I don't see Rushmore for paper actually. I would see them for learning some new skills which doesn't matter if the paper is used.

I think a real diploma has to stay below $1000 to be attractive.