I wouldn't be surprised if a lot of this has to do with the policy at the gas station too. It's not the CC companies that impose pump limits (e.g. $100), it's the gas stations so I wouldn't be surprised if it's the gas station that decide if the CCs have to be ZIP verified too.
I'll try the xxx00 next time we're in the US but I usually just leave a card with the attendant and get them to authorize it for a bit more than I think I need (I've only had one gas station tell me that they can't refund any excess amount - usually it just goes back on the card automatically (i.e. I tell them to authorize $350, I end up only pumping $292 and the card is automatically refunded the extra $68)