Awkward Baby Shower situation

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So one of my aunt's is throwing my bf and I a baby shower at my grandparent's house. She really wants it there because they have a huge party room/bar we can all hang out in and they also have a nice, big yard where the other kids can safely play. Here is my dilemma...My grandparents frequent their local bar and have some of the weirdest, slimiest bar friends that I KNOW will get an invite to come over and hang out. I want it to be strictly friends and family but feel it's not my place to tell my grandparents they can't ask their friends to come over. Should I just ask them not to or suggest a different place to have the shower?