Only... they never qualified for the tax breaks in the first place. The point of the exemptions was that if you come to the UK only to compete in the Olympics, or as a journalist to cover them (or if you're a company sending people to do such things), then you won't have to pay UK tax on your income - it removes a barrier to people coming. And as the UK wouldn't have collected the tax if it weren't for the Olympics, as you wouldn't have come, the UK isn't losing out.
As Coca-Cola etc operate in the UK through UK companies, these breaks for non-residents never applied: they're "waiving" a right they never had in the first place. So, er, why all the fuss?
And why are campaigners crowing about it? Could it be that they are in fact tilting at windmills? I do wish people would try to understand things that they campaign about.
I think I'll go and publicise the results of my campaign to stop people hunting tigers in Wiltshire. Might there be an OBE in it for me, if I can show that no tigers have been illegally poached there in the last 10 years?