What is starting pay for host at Olive Garden?

It's usually minimum wage, which varies by state, plus tips tipped out to the bussers by servers at the end of their shifts. In some areas, it depends how the OG is run, bussers are paid what is called tipping minimum wage, which means they get a lower hourly wage because the difference between that number and regular min wage is made up by the tips they collect. This variation isn't normal though because bussers usually do more than just bus, they run food, clean, help servers/bar/back of house, etc.

In my experience, the more attentive a busser was to my tables, the more I tipped at the end of the night.

They have also gone to a "pot" tipping system in some OGs where the servers don't tip directly to one busser who is assigned to their section but to a pot that is divided among all the bussers at the end of the night.