At least you're selling something you're passionate about. If you're not working for commissions (I know they are more common in some countries, in the Netherlands you simply get an hourly wage, no commissions) you can have genuine conversations about music and instruments and your honest passion will either connect to the buyer or not - which is fine either way.

Good for you that you now know you don't want to grow into management positions. It will make the experience more relaxed, making sure at the end of the day your energy is still up, so you can be present here, you know, the only place we really want to be ;-)

Good luck <3