Just gonna chime in here and share my perspective/experience. I agree with others that I think how leggings are worn depends on several factors including age, region and for what activity.
For example, I live in the greater Los Angeles area and many, many young women (think Middle School up to early 30's) wear leggings with Cropped tops (all the rage at the moment). Think Nicki Minage, Iggy Azalea, Cardi B, etc. In my neck of woods there is no shame in showing off one's "booty". However, this way of wearing leggings is as a casual outfit - NOT in the work force.
I think as one goes up the age bracket leggings are worn in different and perhaps more modest ways. I work in a very professional environment and several years back HR put out an updated dress code (mostly for para professionals and clerks) who were wearing leggings to work as pants. It was not acceptable in that particular environment.
I have to say I do not see many women wearing leggings with tunics in my neck of the woods. Denim and trendy jeans are more popular.
Lastly, I see women of ALL ages wearing leggings as their workout gear and running errands. I see cropped tops, workout tops - but nothing so long as to cover the bottom as much as others mentioned.
So there you go - food for thought. I think it depends on where you live, your age and the environment in which you will be wearing said leggings. All the best to you! cheers