Beside the point, but I was taught that riding a donkey at that time was a sign of his nobility, not poverty.
Exactly right. In fact, it is agreed by most historians that Jesus' arrival on a donkey was to mock the high priests. This was enhanced by the throngs of people laying palms before him. He was entering the Holy City for the Passover Festival as an actual King would. It was the beginning of his week of agitation in Jerusalem. It's the beginning of what got him killed.
Jesus was an activist (of the good kind). He was a leader, a man of action. He got the job done.