If you believe their privacy policy, nothing.
Optery does not sell or rent personal information to any third parties for any purpose. Optery is not a data broker. Optery does not have any financial relationship with any data broker. Optery is not affiliated with any data broker.
That’s why you flash the vacuum with a custom firmware!
It probably is the the best bang for their buck. I doubt they lose significant profit from the simple stopgaps.