If Amazon is promising to pay you at least $36, then the "base pay" must be $36 - that's what you'd be getting if there was $0 tips - and either you're getting all the tips (i.e. if there's any tips, you're paid more than $36), or Amazon is lying and stealing tips (i.e. if there's $2 in tips, they reduce ("steal") your base pay to $34 so you're still paid just $36).