First - I am surprised to hear this vendor can make enough money to pay a $90 daily fee, and a profit. Good for them.
But if the city used to have 10 vendors paying $90 a day, and only have 3-5 vendors paying $90 a day, I can understand why they don't want to pay for the security guard anymore.
Since the vendors in the Mission are also displaced, maybe this is a good time to create a new flea market.