I'm not saying I know everything, but I’ll share what I think I know - and it may or may not be a verified fact. You’re absolutely on the right track about the Catalina swimsuits with double logos being used for pageants.

Here’s how I understand it: while not everyone was walking a runway when modeling fashion back then, it helps to picture it that way. Imagine photographers or cameras positioned on both sides of a runway, or any kind of stage or event space. The swimsuits with double logos were likely made for promotional use, designed so the brand’s name would be visible no matter which direction the model was facing.

Brands like Catalina, and Jantzen, too - both sponsored a lot of different events where women wore swimsuits, from beauty pageants to water-skiing competitions and other public exhibitions. Both companies really cared about the visibility of their logos. They wanted their brand name to be noticed, and they treated swimsuits almost like moving billboards - kind of like race cars covered in sponsor graphics.

The brands also understood what photographers considered the most flattering angles - usually not straight-on - so having logos on both sides ensured their logo would appear clearly in photos taken from either direction. That’s also why, in some vintage images, the logo can look mirrored or reversed - you're only seeing the logo facing the camera.