It’s certainly easy enough to verify whether or not a venue’s certification is up-to-date. Just call whoever they say they’re under. For example, if they say they’re under one of the Vaad’s, ask a Rav in that Vaad to check it out, or call the Vaad.
Maybe people who have more contact with the non-frum world are more sensitive to dealing with non-frum people, be they friends or family. So, Mr. QuestionForYou, looking at that from the perspective of someone who’s very involved with kiruv, I see opportunities to show that the frum family isn’t stuck up, as many NYF perceive them to be. How hard is it to wish someone a Mazel Tov and be mentsch? I recently made a rather long trip to wish a non-frum couple a mazel tov at their engagement party. ANd you know what? The kallah asked me to help her with the Jewish aspects of the wedding ceremony and recommend a book for her to read. That’s a beautiful encounter, that can’t happen if we always think everyone who doesn’t wear exactly the same type hat as us isn’t good enough to stand in the same room with.