I started out in the household goods industry as a lumper. I was taught by owner operators and learned to treat my equipment and my truck as if I owned it.
Yes, I hear it all the time. "Why are you polishing your truck? It's not yours?" "Why are you wasting your money on that truck? It isn't yours?" "Why do you care what that truck looks like? It's a company truck."
My response? "I am in a rolling billboard. It reflects on me as a person and a professional. It also reflects on my company. This is our home. This is where we live. It should be as clean and nice looking as a house."
First impressions leave lasting impressions on everyone who sees your truck. Put yourself in the shipper/consignee/broker/company owner's shoes. Are you going to want your high-end, expensive freight on a truck that shows it's taken care of and the owner has pride. Or would you prefer it be on a truck that has dirt on it from three years ago, the floor and dash are a miss, and where is that smell coming from?
And on this note (now that I've left you with food for thought). let me close with the words of Al Fry and Jamie Jones (my deceased cousin), "A clean truck is a happy truck."