When I'm hiring, I respond to each and every resume. 99% of them get a canned "Thanks for applying. Unfortunately, it's not a match, but we wish you the best of luck."
Is that so hard?
My personal answer? No. It's not.
You're programmers. Write a macro. Then tap the key.
> No company wants to pay someone $25,000-$100,000 a year to reply to the Johnnys of the world ad infinitum.
First, this is ludicrous; even if you're sending thousands or tens of thousands of these letters, you can have a process that doesn't cost but a penny or two more than REVIEWING the email in the first place does.
Second, any company that can't design good processes that work well and cheaply isn't a place where I want to work.