You could say the same about "direct to advertiser PPC" - people who use adwords to bid on keywords, then drive the traffic straight to other affiliate programs, and skim off the profit. Yes, on the one hand they are parasites, but on the other, they are doing keyword research, generating more sales for the merchants, etc. They are value adding.
Granted though, search arbitrage is not in the same boat, and doesn't really benefit anyone.
But what really irked me about the article was the pseudo-nationalist tone. "Who cares if they were parasites? Those were canadian parasites that Google killed!"
I agree it was written a bit like you say though.