It shouldn't be YMMV. It's either uniformed employees that can't do an easy job correctly or managers being douches and making up their own rules. All stores are supposed to accept those if they come up. Of course, there's basically no GS customer service right now so good luck complaining about it.
Not to mention, why the hell does GS still have a store inventory checker if it hasn't been working for over a month now? What's the point? And why do random pages of games randomly disappear?
But you know what pisses me off the most? That "load more" button. It made going through the bumped values list a chore. GS used to have a good website then they changed it to a site that's broken half the time and annoying to use the other half.
You complain a lot, so maybe this will at least shut you up regarding the last point.