I managed auto dealer Parts Departments for several years and I saw my share of tough customers.
Had a guy call me on the phone and he was irate because he said I sold him the wrong starter for his air-cooled Volkswagen Type 1. He had driven a distance to make his purchase.
I apologized and asked the man to bring his old one with him when he returned.
He was still a little hot under the collar when he arrived and slammed his generator down on the parts counter, complaining it wasn't that #$@% easy to get it off!
I took a couple steps back from the counter before I informed him that I sold him the correct starter and what he removed and brought in was the generator. He forgot to appologize or thank me as he spun around and left.
Although they take a lot of heat, it's not always the parts guy's fault when wrong parts are sold. You might be surprised to find out that some backyard mechanics don't know what they're doing.
Since the guy in the newspaper didn't realize it was the "wrong part" until after he paid for it then I'd bet he didn't have his old part and that he bought the part and left with it.
Furthermore, he could have asked for the wrong part, given the wrong make, model, and/or model-year to the parts department. I've seen it happen plenty of times.
I'd be willing to bet the guy in the article has problems with things other than just car parts.