Vintage PR Shots: What’s With All The Dog Dish Hubcaps?

Two beautiful 1961 Impalas, showing off their sleek new rear ends, and both have dog dish hubcaps? Seems so unlikely, especially so for a convertible. Back in the day, one would not see this.

Here’s the other one:


Same color, but the new four door hardtop style. And the hub caps.

Why would they choose to do this on these PR shots? Odd.