I suspect that if a company really wanted to hide something they probably could. So unless you install windows or another OS on it yourself, you don't know what the manufacturer put on it.
I guess it would not be too hard to find in general if it shows up in the list of processes, but they could make it quite obscure and hard to find.
But yeah, I agree that this is quite an annoying move from Lenovo. The least they could do is make it opt-in instead of on by default.