1. The $5 symbol on the back of a show tile is the bonus you get for previously performed shows when putting on a new show. It doesn't cost anything extra to repeat a show you've already done, but you don't get the bonus for it.
2. Left over starting assets are set aside and used to replenish the market before drawing regular assets from the bag.
I think the OP was asking about left over starting events, not assets. You are correct regarding starting assets.