Because:
It's not US made, and this is a US board mainly. The Suzo is/was very widely used here in Europe. Excellent quality and it plays fine. I was "raised" with these sticks and love them. I had the (leaf) home version since 1983 for the Atari 2600 and that one still works great !
There's only one stick better IMHO and that's the Inductive by Suzo....same looks, but NO switches. 2 are on my Mame machine and they are a dream to play....
I've got a couple of the one you're selling in spare here so I have no interest in it....sorry :S