To veteranary doctors get paid based on the treatments they push on your pets?

Your vet is trying to get you to do the right thing for your cat to make sure that it isn't sick, but when you refuse to do so, they can't FORCE you to do it or convince you to, they can only make suggestions. Vets are nothing like auto body shops, that's like saying that you wouldn't get yourself tested for cancer even if you found a 3 inch lump on your head that continued to grow.