Not Obvious

I walked up to the checkout counter.

There was 32 lb bag of charcoal under one arm and a 16 lb bag of ice under the other.

I bet you can guess which arm was most uncomfortable.

I slumped my load onto the counter. The cashier started to ring it up. She asked if I wanted paper or plastic.

I replied, "No bag please, I'm on a bicycle."

She glared at me like I was crazy or something.