I've always saved paper bags. It's what my parents did. I remember my MiL commenting on it as well as my washing out of glass jars and hanging washed out plastic bags on the line so they could be re-used. I still do it.
There's no doubt she thought it a waste of time.
I just let loose fruit and veg roll around the trolley with the rest of the shopping and group them together on the conveyer belt.
I can't believe my car insurance has risen by that much!
They don't really care do they