I know but on instagram they said that they never planned on making more, and that was before they released to button.
Plus, what is a spintop button?
They released the button when they released the tops hun, I think you are getting it mixed up with the second wave of the buttons when they released.
O.
My bad!
But still, what is a spintop button?
with tops you have “weight” at the end of the string called a button. I think this helps with tricks and just holding the string
So, a counterweight? 
basically they got away with by saying it was for tops.
No. It’s best if they are really light. Some people just make a slipknot and put the string around their finger. It’s not recommended, though.