sorry, I'm gonna disagree.
I have NEVER seen any animal die from being fed GOOD replacer - calves, kids, lambs, foals, piglets, kittens. And as I said, I have raised hundreds and hundreds over the years.
I raise orphans for a LIVING. So I do know whereof I speak.
Now as you said, replacer most of the time is cheaper than purchasing cow milk for human consumption from the store. Yes, thats correct. Now why should it matter if you have 2 or 20 or 200 kids to raise? Call me stupid, but even when I have only two or three on the bottle, I still want to raise them in the most economical way. And if your two options are cows milk from the store, or replacer, the choice is simple.
Now, if you can get excess milk from a dairy, or produce your own milk, 90% of the time that works out cheaper than the replacer and cheaper than buying milk from the store. At various times I have had both dairy goats and cattle for raising orphans, but the majority have been raised on replacer.
The key with replacer is not to get the cheap stuff. You need something that is at least 20:20 protein:fat. I personally use one that is 28:21.
http://www.probiotec.com.au/Probiotec/page.aspx?pageId=e58f768e-f8af-4af5-aa30-c7db29d5011c
I use the green