"But you have to price things carefully to avoid outright soaking of customers"
Who is doing that, though? With the subscription services I've seen, the total cost of the subscription is always greater than the cost of the same software as a native application. Even more so when you consider that it makes it impossible to decide to stick with an old version and no longer buy upgrades.
I certainly haven't seen all of the subscription offerings available, but I haven't actually seen one that doesn't seem like it's soaking the customers.