Okay, we've established pretty solidly the fact that sex sells in advertising, but the principle extends beyond that. If you're a opening a new business in the 1950's or 60's, you probably want to have some hot mama in the photo opportunity. Let's face it, no one's going to give two shits about you new mobile home dealership (see image above) unless you've got a leggy bombshell somewhere in the picture.
These days, this might be considered objectifying women and a crass and low-brow way to open a new business.... but not back in the day this was par for the course. Take a look through archival photographs from you city, and you'll be hard pressed to find a ribbon cutting ceremony, ground breaking ceremony or building dedication which DID NOT feature a smoking hot babe.
Let's face it, no one really cares that you're opening a new shopping center. However, stick a lovely lady in the photo somewhere and you've got our attention. Instead of "Ho hum", it's "Hey, honey. Look, they're opening a new Thom McAn, isn't that great!"