Take on the difference between cash and credit

I love getting gas in jersey, even if it's watered down more than a
margarita a TGIFriday's (unless you know the bartender). You don't
have to get out and get your hands dirty plus it's easily $0.40/gallon
cheaper than CT or NY gas. How they can handle this is beyond genius
because you get more gas for your money while also getting a service.
The only problem is tipping. The real savings in NJ gas is to pay
with cash because it chops off another $0.07/gallon so all of a sudden
you start contemplating the real 'savings' because whenever you pay
with cash there is an expectation to tip
The thing is that when you pay with a credit card, tipping doesn't
feel so expected but when you pay cash it really feels awkward to not
throw the dude a buck. So I pull up and have the guy throw in $30
which gets me about 9 gallons on Jersey's finest and then I tip him a
dollar. But this really works out badly for me because I saved $0.63
by paying with cash but spent a dollar on a tip so all of a sudden I'm
down $0.37 PLUS I spent all my cash