Well, yes really. If it is 2 days, and you've bought it online then you can just bring it back.

ishouldnotbutk8's message was mostly a joke since your argument would work with 15 days instead of 2. And yes, customers should be protected* against altering the deal.

Especially that it is so so common now, with the wide-spread of IT. Companies just push out malicious updates and changes in terms and conditions.

* they probably already are, but not many people try to bring remote downgrade cases to courts