Funny you should say that, I actually noticed the same problem when looking at USA1's covers. Take a look at the pick they posted of their cover, when you click on the cloth and vinyl seat cover:
https://www.usa1interiors.com/1981-8...ntal-band.html
You may have to click the tan one to see it better, but there at the top you can clearly see the same problem you're pointing to in those images. This is the reason I've decided to just make my own, and probably why auto upholstery shops are actually the best bet for maximum quality. My old worn out cover from 1987 doesn't have that problem.