I agree they should pay on profits, I'd just rather have them here contributing to employment and employment taxes, than have them move elsewhere if we tighten the system outside of the rest of the world. To be fair you clearly understand that.
As an accountant I know that it's going to be almost impossible to stop transferring corporate profits around in a legitimate way, where as with HMRC there's nowhere to hide. Any employee benefit or reward becomes immediately taxable in the UK at the full rate, you can't transfer that away. In my view it's the lesser of two evils, whereas only a global corporation tax rate will prevent international profit transfers.