Do you ever assume some customers are going to commit crimes with the items they purchase?

Today, a old man was acting grumpy but calm.

I rang him up and he bought some insect killer spray. An aerosol can.

Then he asked me if the can of spray has the potential to injure eyes when sprayed directly on eyeballs.

I said, "If it is kills bugs, I do not think it is good for the eyes."

Then he bought a lighter.

I told him my common farwell phrase I say to departing customers and it is "Have a fantasic day."

Then he told me that the day will "not be good."

I was worried about him hate criming me but I stayed calm and put all his items in a bag calmy. Then went back to fixing the aisles.

Idk about you but all I know is a spray can and lighter can be utilized like a flame thrower.

Am I being paranoid?