Since it's a daily sweeps I would consider using the contact form on the Hunt Brother's website and inform them of the discrepancy you found between the rules and the entry form. They should try to resolve it since they, as the sponsor, need to honor their rules.

Contact Form Link: http://www.huntbrotherspizza.com/contact_us

The only other alternate is to start doing Mail-In Entries instead of online.

Best bet is probably to contact the sponsor and see how quickly they can have their webmaster update the entry form.