it would depend on relative – sibling/inlaws cousin etc.. The closer the relation theeasier and appropriate it would be to move it on your own or ask to have it moved.
I know if I would be host of where you stayed I would not be offeneded in anyway if you would have asked to move or let me know that you moved it out. I once moved something from a bathroom of mine because I had a guest that I knew was sensitive viewing such material. i told my wife to put it away until after they left.