In his WSJ column, Dan Ariely does half-facetious Q&A from the standpoint of a behavioral economist. Alas, instead of sticking to economics, Ariely can’t resist the temptation to turn into Dear Abby from time to time.

Case in point. In the June 11 column, someone asks about a gift for a 45-year-old coworker.

Dan recommends getting the person reading glasses. I’m not making this up. He says people delay getting reading glasses because they don’t want to admit they’re aging and/or they don’t realize their vision is deteriorating.

“If you give your friend a pair,” says Dan Ariely, “you will spare him the procrastination, and he will immediately realize that he has been living in a blurry world. He might not immediately feel deep appreciation, but it would still be a very helpful present.”

Here’s how I responded in the Comments:

Glasses to a 45-year-old? You are saying that the only factor in choosing a gift is the person’s age, and then adding a false stereotype about age.

First, the stereotype. Not everyone needs reading glasses at 45, 50 or even older. Reading glasses have to be chosen for the individual’s eyesight. So the idea isn’t even practical.

Second, if someone asked about a gift for a gay friend, would you recommend Judy Garland records or a rainbow flag? Doesn’t your coworker have an identity beyond his age?

For anybody’s birthday, your gift choice should be guided by your friend’s interests if (and only if) you know them. It’s insulting to give a tea set to a coffee drinker, or to give a box of candy to someone who’s allergic to half the ingredients. Give an Amazon gift certificate.

Dan Ariely would never be allowed to take a dig at statuses like being black, Asian, Jewish, or gay. Yet an insensitive, equally objectionable reference to age? No problem.