It's basic economics. Football generates revenue that supports their salaries. The other jobs you mentioned are paid from tax revenue which has to be taken from people mostly against their will (lottery aside). If you weren't paying the players then the money just goes to the billionaire owners. If you tax any football related revenues more then the price will go up. Owner's won't cut into their profits. I.E. tax tickets $10 more then ticket prices go up $10 more.
It's the same principle as taxing a grocery store. The price gets passed on to the consumer.