I've written about this before somewhere - yes, I received pretty inappropriate recommendations myself, too. And I've never searched for any "adult" content and don't share my reader with anyone.
I could laugh about it, but only because I don't share the reader and don't have any kids or anyone else who could be offended by these kinds of recommendations.
Mine were about
And I haven't looked up anything that even had the word club in it, either, so I don't know where they came from.
They are gone by now and nothing like that has come up again - anyway that was strange and another reason why you should officially be able to switch off the recommendations.