That is a high end bookstore. Not a paperback exchange. No doubt a lot of his customers are rich libs. So this bit of leftist thuggery will hurt him badly.
I would agree on hurting him badly, but there are so few mortar bookstores existing anymore, that if you chase this guy out....you might not have another bookstore for 20-odd miles.
I am concerned for the owners of Black Swan Books. The hatred and vitriol against them on social media is awful. And, as you say, the financial hit they are likely to take ...
They are in need of support. This is most unfair.