How many rich and wealthy people do you know of actually help others and give back to the community?

I've known both wealthy and low income people who volunteer both their time and money to their community. The only caveat is motivation, that may differ greatly, but the end result is the same.

My wife had a client who was extremely wealthy. She was involved in many community affairs. She chose to remain in the background and did most of the funding. I really liked her. She was quite generous to my wife.

In comparison to middle and lower-income people who do this?

very few

My friend's father donated money so the county could get another drug sniffing dog. 

I am sure there are many.