The pump at my filling station says K1 right on it. The guy I was talking with at the Home Depot said that K1 at the pump isn't as clean as the stuff in the cans at the store. That's the reason for the cost difference according to him. It sounded reasonable to me.
I've always used kerosene from the pump ever since I was a kid and we had the wick type kero heaters to supplement winter heating.