Many sellers prefer the clean look of a white background on their items but don't necessarily have a studio set up in order to achieve that when listing. We typically just use our wood table and cream colored walls as a backdrop, but when lotting up clothes to clearance, it can get too busy to just splice the pictures together. Since I rarely use a background remover site, I have not thoroughly investigated, but I came across this site that automatically removes the background from an uploaded picture: Bonanza Burner (background eraser). No coloring required, although touchups are easy if there are areas that didn't come out right. Since I was using this feature in order to create a clothing lot, I used the Zippy Photo Stitcher to combine them. I found it easy to use, with layouts based on number of photos and whether a side-by-side or collage format is preferred. I didn't spend alot of time searching for "the best" free site out there for these tasks, as these did the job.
Below are the original pics, and the combined lot after just a few short minutes of adjustments in the above sites: