Lift This?

Had a customer request help with a carry out of some cat litter today.
Which isn't that big of a deal....but a lot of customers who request carryouts are rather skeptical of my weight lifting skills when it comes to cat litter and bigger bags of dog food.

I can understand that to an extent because I am rather skinny and small compared to basically everyone else in the store.
But at the same time...I do question how weak they think I am.

Because today, the box of cat litter that needed to be carried out to the customer's car was only around 10lbs or so.
So nothing crazy heavy like the 40lb containers of cat litter that I've carried before.

I mean...I can understand it slightly because the customer was older, and I know that the grandparent aged ones cannot lift as much as they used to.
So I understand it.

But at the same time....
I do wonder why customers don't think I can lift that much myself. 

-Sarnic Dirchi