If you want to get _really_ technical, reducing number of transactions means reducing the gas station's cost for credit/debit transactions which ends up with the possible results of reducing the need for stations to hike prices slightly to compensate, or helping keep from driving them out of business. I know while the oil companies are upset at anybody trying to interfere with their raking in of billions, I've seen stories about actual gas stations whose margins are so incredibly thin just to be able to sell competitively that they're barely staying in business. Not sure how common that is, but.... Either way, even if we don't pay more for the purchase, it does cost the station per transaction for plastic (vs cash), so there is cost associated with it...

And as to the cruise range issue... I wouldn't be too surprised if your cruise range won't go up if you don't actually go beyond it. If every time it tells you you can go 550 miles this tank, you actually fill up before you go past it even if you could actually go further, it might decide it was right, hehe. And remember it's always going to leave a solid margin for safety by underestimating the cruise range. Remember nash went something like 750 miles on the tank when he ended up with the 700 mile cruise range.