Your gripe, in this case, isn't with EZ Air; it is also with the airlines. Once the booking is paid, the power to upgrade is in the hands of the airline. I know firsthand, as I booked ours, and desired to upgrade. I was told that, if prior to payment, I could go in, cancel the air, and rebook, choosing business/premier economy as my preferred; other option was to pay for the air selected and contact the airline to bid for an upgrade or pay for it directly. As you see, once the air is paid for, it is all up to the airline to let you either bid or pay for the "enhancements".