The water seller offered him double tribute to take out the biker gang. The old Boba would have just went for the money, but instead he hires the biker gang and tells the water seller to stop price gouging. Boba doesn’t want to be a part of the old corrupt system. He’s not in it just for the money or power. He wants to be a respected leader and win the people over. I’m sure he and his group will prove plenty formidable when the time does come to fight. There’s respect in that too.