And while we’re at it, we’d might as well blame Henry Ford for the problem of drunk driving.
I like people being able to do a websearch on comments on my weblog posts, as I’ve found a lot of very useful information by searching on weblog and mailinglist comments. It should really be up to the various weblog implementors to put in some sort of anti-spammer protection into their comment entries. After all, nothing prevents some big spamhouse from writing their own spider for finding comment forms (which is what they did before they got lazy and just used Google).
Google didn’t create the spam problem, and IMO it’s not their job to fix it either.
There are plenty of easy quick fixes to the spam problem, and why weblog comment engines still don’t use something like that by default mystifies me.