Why Do Michiganders Add an ‘S’ to Meijer and Other Businesses?

How many times have you heard someone say "let's go to MEIJER'S" or "let's go to KROGER'S" or "let's go to PENNEY'S"?

Michiganders are notorious for adding an "s" on the end of businesses.

Have you ever heard someone refer to it as "K-MART'S"? I have.
Or "BIGGBY'S"?
"VALU-LAND'S"?
"WALMART'S"?
"WORLD MARKET'S"?

Where did this annoying (to out-of-staters...I admit I do it myself) habit come from?

MichiganNative.com claims this habit started way back with employees who worked for the Ford Motor Company, who would tell people they worked at "Ford’s Factory," not the "Ford" factory.

BUT WE ARE NOT ALONE.

According to UM English prof Ann Curzan in an interview on MichiganRadio.com, we are not alone in our sloppy speech: the populace of Missouri, New York, Ohio and West Virginia seem to do the same nutty thing that I thought was unique to Michigan.

Maybe, because of our lazy, carefree speech, some businesses have added the extra "s" to their name: Hungry Howie's, Sensations, Jimmy John's, Wendy's, Trader Joe's, Staples, Consumers and others.

So let's keeps being our uniques usses.