Many years ago, my wife had zero understanding of 'overweight', 'oversize', or 'excess' baggage. On a trip to Indonesia, when I joined her in Sumatra she'd prepared a suitcase for me to take back to the US filled with dried spices and seasonings - it weighed 45 kg! I tried to explain to her that I'd get charged a fortune for overweight baggage, but she simply refused to listen or understand. So I moved half of it to my carry-on to get the checked bag down to the 23 kg limit - then of course I had a 25 kg carry-on. But of course, they didn't weigh the carry-on.
A couple years later, we missed a flight in Las Vegas because she wasn't allowed the five carry-ons she had (and that I'd repeatedly warned her about to no avail). After that the light bulb came on and she's been better behaved since.