There are many reasons why people should give. The best reasons are because donors should want to give, either to fulfill a religious or moral duty, because giving provides personal satisfaction, or even pleasure.

The worst reason to be a donor is because someone who doesn’t have as much money as you do thinks you have too much and “need” to give more. As Alexander Podkul noted here at PD Forum in April, Inside Philanthropy decided that such billionaires as Jeff Bezos, Larry Page, and Steve Ballmer were among the people who “just don’t care enough about the world’s problems to do something with their fortunes.”

Now, the practice of “philanthroshaming” is quite old. John D. Rockefeller was repeatedly vilified both for making a fortune and for giving it away. Labor leader Samuel L. Gompers, for example, declared that the most noble thing Rockefeller could do was to “help other people see in time how they can keep from being like him.”

 As George Mason University’s Benjamin Soskis notes in this Washington Post piece, the most recent target of “philanthroshamers” are the heirs of Walmart founder Sam Walton. An organization called Walmart 1 Percent has decided to denounce the Waltons for a) not giving enough money to charity and b) giving much of its to efforts in school choice and charter schools, which they despise.

It turns out that Walmart 1 Percent is a project of the United Food and Commercial Workers and an organization called OUR Walmart, both of which are dedicated to unionizing Walmart workers. However, a very helpful legal disclaimer at the bottom of the Walmart 1 Percent website says that judges in five states have blocked these organizers from entering Walmart stores. In Anne Arundel County, Maryland, for example, Judge Paul Harris, in a November 2013 ruling, said that these organizers’ activities included “’flash mobs,” handbilling, placards, singing, chanting, stomping, yelling, sound-amplification devices (such as balloons and megaphones), manager confrontations, picketing, and the blocking of ingress and egress to and from Walmart’s private property.”

(Now, remember, this is a judge in Maryland, a deep-blue state, and one where unions have, in some counties, blocked Walmart from building grocery stores in their supercenters because they’d compete with unionized grocery stores.)

Walmart 1 Percent’s argument is that, in their view, the wealth of the Walton Family Foundation was primarily given by Sam Walton and his son, the late John Walton, and that other Walton heirs have given very little. Since they don’t give very much to charity, the group argues, they should let Walmart workers unionize and substantially increase their wages.

Walmart 1 Percent admits that they have no inside knowledge about whether or not the Walton heirs give privately or if they are planning major contributions later in their lives. This is a common mistake “philanthroshamers” make. The best known example  is Andrew Mellon, who was indicted in 1934 on tax fraud. The IRS claimed that Mellon was buying great art, taking substantial deductions for his purchases, and then keeping the art in his house for his private enjoyment. In fact, Mellon was acquiring the core collection of the National Gallery of Art, which he was doing secretly because he wasn’t a donor who liked the limelight and because he thought he’d get better prices from dealers if they didn’t know he was building a national collection. Mellon was forced by the indictment to reveal his plans, and the courts ultimately acquitted Mellon’s estate in 1941—after the National Gallery of Art opened. (I discuss this incident in my review of Sir David Cannadine’s Mellon biography, which appeared here.)

As Soskis notes, you ought to ask why donors give and why they give rather than grading them solely on the amount of their donations. “Philanthropic accountability is more than balance sheets,” he writes, “its imperatives are not satisfied merely by knowing how much billionaires give but in scrutinizing the objects of their largesse.”

Evaluating philanthropy isn’t an easy task. But it’s much more complex than the philantroshamers’ method of counting the number of digits on the check—particularly if the group conducting the “shaming” is an organization that thinks screaming at shoppers wanting to save a few bucks is an honorable means of persuasion.