I wouldn't put it that way. I assume they are only doing it by default for some folders like ~\Desktop, ~\Documents etc. For the average user this "feature" must be transparent in the sense that mostly you won't notice that this "feature" is in effect. Just that the onedrive daemon is gonna be syncing changes to these folders to the cloud. They will only notice this "feature" when they get a notification saying that their cloud storage is running out of space to sell them a subscription to expanded storage space.