Because they pay you for the work? You can use the money to further your political goals. If you go to a pizza place and pay for a pizza, you don't expect the

Because they pay you for the work? You can use the money to further your political goals. If you go to a pizza place and pay for a pizza, you don't expect them to alter the deal after you pay, and instead give the pizza to someone homeless without asking you or refunding you.