How about Apple.
You buy a product from their store, you agree to the license.
Later, if you want an upgrade or re-download, YOU MUST agree with the changes or will not be able to download the software you PAID for. And of course, the only way to back it up is with iTunes.
The terms of service changes at Apples will (which changes frequently),and you have NO SAYING on it. I do not understand how this is legal, but I guess law is in the side of whoever has the deepest pocket.