So not only a service that spies on the sites it is installed on, but also spies on all my transactions, and when it is down I am just going to lose who knows how much revenue because only then I will start to even look into how to make my own shop..... and whatever plugins I wrote will not work with updates from whatever solution I will select because the code is not in them and I will need to start finding a way to notify client which will probably be upset with me.

I truly don't get the value proposition here. You need to be extremely small to even take such an unneeded risk.

yes it can take time to understand how EDD software licensing works, but it probably takes more time to design your "store" site.