That doesn't make any sense to me. If the players agree to restrictions and then actively try to subvert them by trying to find a loophole, they are being disingenuous and shouldn't have agreed to the original restrictions (as is of course their right). Why wouldn't the unhappy player just tell the DM they don't want to play that way?
Or it could just be that the players aren't trying to be combative, but simply see the restrictions as a new challenge to be overcome with ingenuity. They might not even be aware that they aren't playing in the spirit intended.
In my experience, gamers are more likely than average to be unaware of such things.