So long as you keep it a secret, it is going to be hard to get feedback or make any money at it. If you do it and it is a good idea, no doubt others will copy it. It is inevitable.
The idea is to be good at it and if you are first, then you have a head start.
Suggest you try it out on a small scale and see if it works. Test marketing is really the only way to know if you can make it work.
Just checked our bank account, we can retire today if I stop spending money now.