Read the digital millenium copywrite act.

Just because you "agree" to the license on/in the package doesn't supercede the law.

Under the digital millenium copywrite act you are legally able to make a backup copy AND install software on more than one computer at the same location as long as the two computers are not running the same said program at the same time. The only way for a company to guarantee such is to provide a hardware lock that you plug into a port into the computer that must be present to run it - if they don't provide one you fall under the above said law.

You can sign a piece of paper "saying" anything and agree to it. Doesn't mean you give up any rights even tho they are listed. You can't 'sign away' any rights here in the US.

In fact if you read the license I'm betting it says somewhere to the effect that "unless superceded by local/state/federal law" or words to that affect.