some people prefer the quilting part of quilting over the piecing part-so yes- people do buy tops-
they do not pay alot for them-
if you want to sell your tops you should figure out your costs- then determine what you think would be (fair)
if you do not get any responses you will know you are expecting too much- you need to remember- a top still needs a backing and batting and all the work of quilting/binding- you will not make alot just selling tops- but it is a way to get rid of them if they are stacking up.