If you try to activate again soon after a previous activation then it will make you call their activation call center otherwise it will just do it over the internet. For legitimate users then at most you just say you're reinstalling your PC and they'll give you the activation code. They do allow you to do multiple activations though. Not sure where you heard that they didn't.

If you're calling up every day then they're going to ask what you're doing and refuse to give you the activation code. It just weeds out the really blatant violations like somebody using a single key for an entire office or somebody posting the key online somewhere.