That's the point. I'm of the opinion the majority of porn "consumers" do so solo. Repeatedly. While it's possible some "consumers" will get appropriate health tips, I'm thinking they're in the minority. And I'd be surprised at any data showing "kids" learning "safe sex" techniques by watching porn. Far more prevalent are the age old clichés: "virgins," "cheer leaders" "school girls" etc. Or, to put it another way, I believe the horrific STD transmission data would be influenced only microscopically by condom requirements in porn flicks. But it's easy to get the majority to favor ineffective, unnecessary regulations for an "industry" that provides guilty pleasures. Helps that feeling of moral superiority.
If the societal efficacy of condom usage in porn flicks could be established, then shouldn't we also confiscate all the porn that's already out there where condoms aren't used?