“Workers of all lands unite,” reads the marble engraving atop Karl Marx’s grave in London. But if said workers were to congregate at the tomb of their advocate, they’d have to part with some of their capital: It costs about $6 to enter the portion of Highgate Cemetery where he lies.

Some modern-day admirers of Marx who want to abolish private property are understandably upset that it’s not free to get in. “There are no depths of irony, or bad taste, to which capitalists won’t sink if they think they can make money out of it,” whined one 24-year-old Marxist to The Wall Street Journal. Instead of paying, he chose to peer over a fence at Marx’s imposing bust. (This is far from the most bitter reaction the grave has inspired: People have tried to blow it up, twice.)

This is not the first time skeptics of capitalism have been given ammunition when it comes to their intellectual forefather’s burial site. The cemetery’s chapel at one point sold mugs and postcards with Marx’s likeness on them. And, about 20 years ago, the Friends of Highgate Cemetery, the charity that maintains it, permitted an Italian fashion brand to stage a photo shoot around Marx’s grave to promote a new line of sportswear emblazoned with Cyrillic characters.