You must have a bad GameStop. The one near me has the Switch section out front and it's got to be the same size as the PS4 and XBO sections. They also have a decent sized section for Amiibos.
Of course, who knows if your store is basing their layout on regional sales or it is just poor management of that store.
I've always had a good experience at GameStop. Well, minus the hounding about preordering. Sometimes you get a good employee, who knows people hate it, and he'll ask once quickly and be done with it. But, other times you'll get the overzealous employee who asks you, you say no, but will go through the upcoming releases to try and get you to preorder anyway. I know corporate has quotas for them, but God, they have to learn that turns people off from coming back.
I've been to several Gamestops in my area and they all have a small section for the Switch. It is out front at least, but it is always small. It could just be that the regional manager for my area sucks. Interesting to know that the one in your area has the Switch section stocked a lot better. I have to wonder if your experience is the norm or mine is (or maybe somewhere in between).
I'd imagine somewhere in between. It does suck that it isn't as uniform an experience as it should be when going into another GameStop store.