Z symbol for small use

This was part of a bigger thing but I spent hours refining this symbol to work better at small sizes and then it got binned.

It looks like there was a logo that already existed (Zune - thanks for the knowledge @Andrew Martis @Damien du Toit ) but I wanted to raise the issue of selling logo routes that don't make it…

Is that a thing or should it be?
Should I be trying to sell leftovers?
Is it morally right?