IIRC the uniforms DID bunch up quite a bit and yeah Picard did it the most but I do recall Riker and even Geordi doing it from time to time. It was a real-world problem that bled over into the fictional world and in one case became a character meme.
I remember reading an old interview and I think
it might have been Jonathan Frakes who said the very same thing. The uniforms looked
good, but weren't all that easy to wear.