I just fell victim to that too. If you click on it, it takes you to:

www.restauarant.com

which is really a garbage site with popups (and who knows what else)

instead of the intended site:

www.restaurant.com

Now, the bad site basically lists any restaurant (since it links to yellow pages)...

Wouldn't there be a legal problem here as the T&C is sort of a legal agreement?

I can see some lawyer do a class action...the T&C (posted by the OP) say:

$50 Restaurant.com certificate Terms and Conditions
Member will receive two (2) $25 electronic dining certificates from United via a valid e-mail address, each valid for $25 off dining expenses at participating United States restaurants listed on the www.restauarant.com website.