A transcript of a September 20 National Public Radio (NPR) story highlighting a good deed of a Dairy Queen manager grabbed my attention.

The manager, Joey Prusak, noticed a woman putting a twenty-dollar bill into her wallet that a blind man had accidentally dropped. When she refused Mr. Prusak’s request to return the money, he refused to serve her and gave the blind customer twenty dollars from his own pocket. Another customer reported the good deed to Dairy Queen by e-mail, which was forwarded to the owner of the store who posted it where everyone could see it. Another employee posted the good deed on Facebook, and it eventually went viral.

And the rewards started swirling. Customers appeared from miles around to give Mr. Prusak money. Glenn Beck invited him on his radio show and offered to buy him a franchise. Warren Buffett, whose Berkshire Hathaway Inc. owns Dairy Queen, thanked him by phone for being such a good role model. The Wild, Minnesota’s National Hockey League team, offered him a suite where he’ll be able to watch a game with twenty close friends.

“The guy did a really nice thing,” I said to my wife, Lisa, after telling her the story. “I’m glad he got recognized, and that the media reported it; there’s way too much bad news out there.”

“I agree,” Lisa said, swishing her brush through her hair.

“But,” I confessed, “a couple of things disturb me.”

“Like what?”

I talked about my fear that this incident taps into the “blind-person-as-either-pathetic-or-amazing” stereotype.

“Yes, but blind people are at a disadvantage,” Lisa pointed out. “It’s harder for us to know if money has fallen out of our wallets.”

“True,” I conceded, “but I can’t help wondering if the same recognition would have happened if the bill-dropper hadn’t been blind — or should that matter?”

“I don’t know,” she said slowly, spraying something on to herself. “But it’s just the way things are.”

I then told her about the dangers of giving too many rewards for a good deed, as one of the most thoroughly researched findings in social psychology is that the more an act is rewarded, the less interest the doer will tend to have in repeating it. “But everyone’s different,” I continued. “Some are influenced more by money, vacations, and other things than others.”

“It does seem a bit much,” Lisa said, sitting on the bed, “but it’s not the manager’s fault that he got all this recognition.”

“Of course not. But we want to see more of these good deeds, and this excessive rewarding probably doesn’t help.”

“I hope he enjoys his perks,” she said, heading out the door for a visit with her friends.

We hugged briefly. “I agree.”

“Because I worked for Dairy Queen when I was in school,” she reminded me, “and it wasn’t a fun experience.”

Her comment triggered a third concern. The NPR story reported that a Dairy Queen spokesman had said that “the company is figuring out how to reward Prusak.” Research and common wisdom shows that, whether influencing guide dogs, kids, or employees, the closer the reward to the deed, the better. I think that the storeowner’s quick action and Mr. Buffett’s phone call were enough, but I hope the merchant of blizzards is better prepared to reward future good deeds of employees more quickly. I believe that it would have been much more powerful, for example, if that “suite-for-him-and-friends” perk had come from Dairy Queen instead of the Minnesota Wild.

I hope that the customer who is blind has the chance to personally thank Mr. Prusak, if it hasn’t happened already. I hope the bill-stealer is sufficiently shamed. I hope all of us — parents, teachers, managers, and executives — do better at rewarding good deeds when they happen.

And thank you, Mr. Prusak; you’ve done good.