The point is I am not talking about targeting one specific address and finding collisions, but about targeting "every address", just generating until you find addresses that hold BTC to some extent, and taking whatever it is you find on the way.
I think it is semi-possible.
while going for one address is unlikely to the extreme, just going after multiple random addresses is much more likely..
I was testing keygen and memory once, and I had bitcoin generate 1 million keypairs.
If a botnet was to do this scheme, I would think that there would be a good probablility of getting a small few. however the likelyhood of getting a single address with a large amount of bitcoins, is as impossible as attacking one address.
I also wonder how many addresses most people have..