Kill them with #4s. It isnt that big of a deal.
You will end up with a bigger hole in the breast than you're used to seeing, but it all grills up the same.
It doesn't remove any meat, it just puts a hole in it. I don't really care if it has a hole in it or not.
So far as wasting a shell, I don't see it that way and I am super cheap. If you were to ask me to trade a box of $7 Remington steel shot shells for a limit of doves, I would take that trade right now.