Instead of pushing the (debatable) cost savings, what should be pushed is the quality benefits of the WSE system.
On the other hand it is not all bad, there is a good justification for considering these blades – it is a pity that it isn’t this aspect that isn’t being pushed. Keeping in mind too, these are consumables, not something intended to last for years.
Wouldn’t seem to offer much of a cost saving, and it would be rare indeed for someone to own more than one type of machine to want to swap the blades from one to the next.