If you have not yet purchased weekend passes for the 2017 Cubs Convention you just might be in luck - if you have a MasterCard! MasterCard has made available 50 pairs of weekend passes through their Priceless benefits program.
Go to https://www.priceless.com/en-us/unitedstates/2017-Cubs-Convention/offer.html for an opportunity to purchase a pair of passes for $216. That's face value! (The passes are only sold in pairs.)
When you complete your order, you will receive a voucher via email that can be exchanged for the passes at the registration desk.