There is absolutely a difference in how rich and poor people treat poor service workers.
It's not that poor people treat them better per se but it's different. Poor people can be cruel to each other because they are all suffering, crab in a bucket shit.
Rich people mostly ignore poor people because visible poverty makes them uncomfortable so they look away. They hate themselves if they see our humanity so they try not to.
I've been on both sides of this and am speaking from painful experience in both cases.