DEAR CAR TALK: I went to a big-box store to replace my tires. They removed my hubcaps and placed them in my back seat.

I did not notice until I was home. I am going back to have them added to my new wheels.

Is there a reason why they would not put my hubcaps back on? Thank you. – Pat

RAY: There are a couple of possibilities, Pat. One is that they forgot. They’ll typically put the wheel covers in the back seat when they remove them so they don’t lose track of them or confuse them with the 78 other wheel covers lying around on the garage floor.

And it’s possible that whoever was working on your car just spaced.

You would think they (or you) would have noticed the absence of the wheel covers, because the car looks pretty unfinished without them.

But maybe he was daydreaming about finding a rare, first-edition 1963 AMC Rambler Shop Manual in a barn somewhere, and wasn’t thinking straight?

The other possibility is that they sold you new wheels that don’t use wheel covers. You mention getting both tires and wheels. If you bought a set of alloy wheels, for instance, you wouldn’t need wheel covers at all.

Alloy wheels, which are forged out of aluminum alloys, are designed as “one-piece” wheels. The design of the wheel itself is part of its appeal. And they look good – and finished – just the way they are.

In that case, the mechanic may have tossed your wheel covers in the back seat just to return them to you: He figured they were yours, and rather than throw them away, he’d let you decide how to dispose of them, or include them in your estate planning.

There’s a small possibility that the store sold you a new set of wheels that your wheel covers don’t fit. But there’s only about a 1 percent chance of that.

So take a walk around your car. If you look at the wheels and see a big, black, industrial-looking steel maw in the middle of each wheel, then they probably forgot to put your wheel covers back on.

But if the wheels look good, and they look shiny and finished, then you probably bought alloy wheels, and you can use those old wheel covers to start some tomato plants.

Got a question about cars? E-mail Car Talk’s Ray Maggliozzi by visiting the Car Talk website, www.cartalk.com.