The ability for Disney/Universal to operate their own subsidary travel companies have allowed them to stay competitive in the market.....a main reason that Disney/Universal packages do not fluctuate greatly in price. If they did not permit it, then companies like Orbits or Priceline would be able to offer package discounts that the company wouldn't be able to itself.
If they raise the taxes on all companies, trust me, that cost will just be passed on to the consumer. Our government officials like to make sound bites villifying about how profitable a company is and the tax breaks they receive, ending with threats to remove the tax breaks. But, in the end, those increases in tax will be passed on to the consumer, not taken out of the profit line. Look at all the fees, taxes, etc in almost everything you have (rental cars, gasoline, cell phones, land lines, cable bills, etc). No company will absorb these costs or taxes.