I think they must sale data in bulk someway. I agree it's a labor of love and I'm not saying they are nefarious in any way, but maintaining a site at that scale is expensive. Particularly with the text message processing.
If anyone wants a local alternative, the Fuelio app for Android...
They were @MSRP with no wiggle room, and so far no added mark ups. I thought about doing the same and ordering elsewhere for the discount, but I don't think I'd be able to fly out once it came in. Hope we get ours eventually lol.