You don't need to have a lot of points to start getting low end perks, you just need an active card with some.

The most convenient for most people is the Harrah's/Horseshoe family.

I used to play a little poker at the Horseshoe casinos near Louisville and Chicago. That would get me discounted or even free nights at places like Bally's in Vegas.

The amount of discount is also going to be determined by how major of a Vegas night it is. You're not going to be getting cheap or free nights the weekend of a big fight because you have basic status.