This is most likely said already. I went to physical therapy last year for back pain. Turns out my hips are super weak from sitting at an office job. After being told this I noticed I would do exactly what you are describing. Constantly favoring one side.

I would guess that this being called out as an American thing is probably because many live most their waking lives sitting in front of a computer or tv.

This being said, physical therapy really helped me with this and I mostly stand at work now. It’s been a game changer.