Threesomes.
Anyone who can't afford to get to New Orleans, or feels bad about whacking off in public, will be intrigued.
If your customers enjoyed Barbarella and Flesh Gordon, give 'em the high sign for Hooligan.
Production values edge out both story and sex here, but customers should buy/rent anyway.
An example of early porn's "anything goes" attitude; retailers' best target will be porn historians.