What I don't understand is this. The person owns the bookshop and is complaining about what is on the shelves.

Aren't they in charge of what they stock?

If they feel so fervently about this why are they stocking (and I assume selling) these books that offend them so much?

If you feel this strongly, empty your shop of all those works that offend you and only stock things that meet you approval and stop your bitching online about something you control...