This whole chapter is amazing. Jesus rode into Jerusalem on a donkey then walked back to Bethany! He was deliberately identifying himself with Zechariah 9:9.
I'm sure they didn't fill the temple with money changers overnight. There was a gradual creep as they adapted ideas that made it easier started out making it easier to for people to worship. One thing led to another and they were stealing from people in the name of God!
I'd like to figure out this fig tree situation. Mark says, "It wasn't time for figs." This wasn't about fruitfulness or cursing. Jesus made it about prayer and faith when they came back and found it shriveled. It is a picture of the level of authority he had and was passing to them. "Ask believing, and you will receive it." What do I really believe God will do when I ask? Not enough, that's for sure.