I've always wondered -- how do movies like this greenlighted? I understand that people take jobs to pay the bills, but how does someone read a script about Radioactive Giant Rabbits Terrorizing the Desert and decided to make it and sell other people on the deal.

In the '70's, studio execs were doing a METRIC SHITLOAD of coke.

Actually, there were a couple of outfits (most notably Roger Corman's film school) that would not only green light a picture like this, if it looked like it could be done for under $10-50,000, but specialized in making cheap-ass films like this.

In Corman's school, you had ten days and ten thousand (I think) dollars to make a bad horror movie. If you finished with time to spare and budget left over, you made another one with what was left over.

There are a lot of bottom-feeder SF movies because movie execs know they can count on an audience that has low expectations.

It's the same thing as the Sci Fi channel's original movies. Which I have discovered are great during a migraine (thank you Brad Johnson and some poorly articulated vivisection metaphors).

In Corman's school, you had ten days and ten thousand (I think) dollars to make a bad horror movie.

Often, you'd start with a title and a "star" of some sort or another (if you consider Lee Van Cleef or Peter Graves stars). Not even a premise necessarily, just a title and a poster. They'd sell the theaters on that, then make the film.

If you finished with time to spare and budget left over, you made another one with what was left over.

Heh, this is what happened when Corman had Boris Karloff and 3 days left over after THE RAVEN, so he drafted Jack Nicholson (who played Peter Lorre's SON in THE RAVEN!) to star, as well as do some uncredited co-writing and directing (and I guess a couple other folks lent a hand in those departments as well). They got the film done, and it's actually worth watching. It looks like a random Poe mash-up. It's not good, but it's interesting.

A LOT of interesting folks got their start working for Corman.

That sounds kind of interesting. Cracked out and weird but still interesting.

Checking imdb, I was wrong about Nicholson doing any co-writing, but he did co-direct, along with Corman, Francis Ford Coppola, Monte Hellman and Jack Hill (all but Corman uncredited).

A LOT of interesting folks got their start working for Corman.

Probably the most notable was Ron Howard. That's where he trained to direct. He has a couple of interesting and amusing stories about working with Corman.

Probably the most notable was Ron Howard.

I'd argue Martin Scorsese (though he had already done one on his own before doing BOXCAR BERTHA) or, as I said, Coppola (who did a couple he did get credit for, notably DEMENTIA 13), as I figure Jonathan Demme isn't quite as notable Ron Howard.

I forgot both Scorsese and Coppola worked for Corman. Yes, Corman has produced quite the lineup of high powered directors, which is HI-larious when you consider the kind of work they were producing.

a METRIC SHITLOAD of coke

Wow, that's, like, Eurotrash levels.

I figure Jonathan Demme isn't quite as notable Ron Howard

I am outraged on behalf of Mr. Demme.

when you consider the kind of work they were producing.

I like that lefty ol' John Sayles got his start writing Piranha and Battle Beyond the Stars for Corman. Edit - just writing, not directing.