I have two reasons for always getting a receipt: (1) as a Virginia resident, I can get a rebate on fuel taxes paid on fuel bought in Virginia; and (2) if I ever get a tank of bad fuel, I want to be able to PROVE who is going to be paying for the damage. HPFP, a full set of injectors, bits & pieces plus labor on my TV could run upwards of $10,000. Dunno what they'd run on your rig, but unless you want to pay it all yourself, get a receipt.
I've never had to fight with an attendant to get one, btw.