Okay, now I see what you're talking about. You're right, that velcro pad has absolutely zero impact on the fit & function of the BCD itself. We actually stopped sewing them onto our shoulder sections a few years ago because they really weren't having a significant positive effect on the BC itself. If I remember right we used that velcro just to try to keep the buckles down flush to the shoulder section, but it was hardly noticeable. After we got a rash of poor adhesive on the backing of that velcro we reevaluated the usefulness of it and decided to phase it out.
If you like I can send you another piece of velcro to attach to the buckle or you can wipe off the glue and carry on like it is, since the "loop" portion of the velcro thats sewn onto the shoulder won't hurt anything if you leave it.