I only wear sports leggings occasionally for exercise, so I can’t really represent the view of women wearing leggings as pants in everyday life, but I guess the main reason is that they’re very comfortable (unless they’re shapewear). I would compare their comfort level to sweatpants.

I didn’t consider that it might look confusing, lol. I also don’t know why the picture was rotated by 90 degrees when I posted it :/