Yeah a lot of people need to give it a rest as some of us haven't even had 1 person sign under their referral. We are supposed to be all about sharing right! If someone signed up under you chances are they will do an offer soon enough. My sig has my referral link if you are feeling generous.
Anyways, I thought I would post a reply I got from their website regarding cancelling your offers.
Hello,
Thank you for contacting us!
You may not immediately cancel the offers as doing so may lead to
credit being reversed or account locked. We do ask that you thoroughly try the
advertisers service. If, after doing so, you do not wish to continue
with them, you are free to discontinue your membership with them and will
retain credit.

Hello,
Thank you for contacting us!
You may not immediately cancel the offers as doing so may lead to
credit being reversed or account locked. We do ask that you thoroughly try the
advertisers service. If, after doing so, you do not wish to continue
with them, you are free to discontinue your membership with them and will
retain credit.