egsshell,
We've obviously had different experiences. The worst airline for checking seat belts in my experience is Thai Airways (TG).
After landing on a TG flight, my wife realized she had accidentally left her seat belt undone. On my next flight, I tried an experiment, leaving my seat belt obviously undone when the crew were passing through the cabin, checking for security, before takeoff or landing. It took ten consecutive TG sectors before an FA noticed and asked me to buckle up!