Newbie trying to help Newer Newbie

At least they weren't arrogant about it. They knew it was un-level and it didn't bother them or they didn't care. They'll learn.
That's better than being next to a know-it-all that doesn't know Jack.
Like the time myself and my Gal went to Mount Storm, WV for my check-out dives to complete my Open Water Scuba Certification. There's camping on the lake, and divers gather there. I met the Dive Instructor at the lake with intentions of camping, but weather was rolling in and I was feeling the start of a cold. It's bad JuJu to dive with a stuffy head, so we opted to stay in a dry, warm motel, hoping not to trash my certification. Anyway, an adjacent group's Instructor was spouting off about how he's camped for years and roughing it is great and been there, dove that, blah, blah, blah. I noticed he opened a big blue tarp under his tent as his ground cloth, and it spread out from the tent at least ten feet in all four directions. I said something about the eminent rain and his reply was something like, "I got it covered", glancing at his huge blue tarp under his tent. Shame on me, but I wished them all good-night and left for the motel, not saying a word about his ground cloth arrangement. Apparently, my Dive Instructor, who stayed at camp, didn't say anything, either. Nor the other 6 or seven campers.
It's a good thing scuba gear is meant to get wet. Arriving back at the camp the next morning to proceed with my dives, his ground cover was a big, balled up, muddy mess that resembled a lake with a tent in the middle. I passed my check-out dives and I guess Mr. Camper Man learned a lesson. Maybe.
It's nice you were kind enough to use your time and energy to try a tactful approach and point out their unusual leveling procedure. Horse to water, and all that.

Hey, we could turn this thread into most knuckleheaded camping disasters!

Sometimes you need to disconnect to get level.. Sometimes you do not.. I gather this time they did.

Of course if you have one of the toys in my basement it helps... I can (With the aid of the things I stow there) pick up 12 tons. (Actually more) or so says the label.

When the fridge quits cooling they'll get a clue about level.

A/C doesn't much matter other than which way condensation from drip pan runs off roof but a little bit of accumulative damage is done every time fridge is operated off level.

Maybe they'll be better informed next trip out.

My bet is that when they get home, they will do some internet searches, find out what you told them was true, and on their next trip, they will level their TT, and watch for a non-leveled TT so they can share their expertise.

It's the way of the world - never let the prior person know they were right, but tell the next person as if you have always known it. :)

Thanks for trying!

All you can do is tell them. They learn, some just take longer than others.

Reminds me of something that happened a long time ago. The very first time I took my kids camping was with a small dome tent. As we were setting up the tent I was explaining what all the parts were for. After we set up, our neighboring camper came over and said this was his first camping experience. He said he didn't know what the extra piece was for (rain tarp) so he left it home.

They will figure it out sooner or later. Your nudge I bet will at least get them thinking.

However there are far worse ways to screw up a trip.

I know from my own experience. :o