I am with Outdoor Girl. Not petty at all.
I have Global Entry and Pre-check. Yes, it was annoying to get and the intrusiveness squicks me. But I just got back to the US and met someone I know in Duty Free on the other side. I did not have a second lounge pass. This person does not travel often and was flying coach, while I was in business, and does not have Global Entry. We talked, walked toward the gate together, and I peeled off at the airline lounge and said, "Sorry, I don't have a second lounge pass." She said, "No problem. Enjoy. I have my car at the airport. Want a ride home?" "Great, thanks, but I have Global Entry so I'll get out faster." "It's at Parking Lot. Want to wait in their lounge -- it is pretty decent -- or catch a cab?" "I"ll see you at Parking Lot, then, thanks." We both have cell phones and know how to use them, in case there was a delay.
No problems, no worries, we visited happily on the ride home. The mere idea that I would sit at the gate for three hours because I could not take her into the airline lounge, or would forego my Global Entry end run so we could visit while standing in the endless line a 747 produces never occurred to either of us. I could also have said, "Thanks for the offer, but I'll catch a cab and call you next week," and that wouldn't have been a problem, either.
I think it is fine to say, "Friend, everybody going this trip has Nexus. If you want to go on this trip, or in a Nexus car, you need to get Nexus. If you don't, take the bus and meet us at Place." Near the borders, phone service is usually just fine without getting an international plan, at least where I cross to Canada or Mexico, so "You have my phone number, right? And I have yours here, so we can update locations when you get through the lines." Most places have day trip buses available. I do not see one single thing rude about this, and plenty that is rude about asking a car full of people to wait in a longer line, maybe for hours, because ONE person does not have a fast access pass.