Why does people on medicaid get more benefits than people in medicare?

Because Medicaid is needs-based, meaning it's welfare for people who are impoverished. Medicare is not needs-based but is an entitlement program, meaning you get it no matter how rich or poor you are so long as you are age 65 or older or been on disability for two years. 

By the way, Medicare is accepted by all, meaning you can go to whatever doctor, no matter how expensive, and that doctor will take it. Medicaid is not. People on Medicaid often have a hard time finding healthcare providers, good ones anyway, because relatively few accept it, a result of it establishing very low prices without negotiation and healthcare providers getting so little that they often operate at a loss for Medicaid patients.

If you're on Medicaid and become eligible for Medicare, you should file for it. Medicaid will pay any Medicare premiums and will pay what Medicare doesn't. The result is you can have the freedom of Medicare in choosing a healthcare provider but not have any of the Medicare copays or premiums.

Medicaid is for POOR people, which is why they get it for free.

Medicare is only for senior citizens.