It may be different, yes, and I can relate to the OP's original complaint from his girlfriend. Still, given the language used on the site and the (albeit weird) use of a "credit" that can be used in the future for each month you don't buy something, it doesn't seem unfair at all to me.
I will say that the negative attention this confusion could bring them is more harmful to them than if they revamped the purchase process to just make it crystal clear what you're buying.
From my experience at Poll Everywhere, the "sidebar" on the checkout process does not get read by anyone, anytime. For some reason, the sidebar becomes a blindspot and is ignored (at least in our testing) during a checkout process and so is thus not a great spot to put reminders about how you're joining a membership and will be charged monthly if that is the only place is is put.