Can someone explain why there are no wing struts on these Staggerwings?

I absolutely fell in love with this Spartan Executive...

This is some kind of Super Stearman. All I can say is that compared to other Stearman's, it is HUGE!

An early Stearman

A drop dead gorgeous Waco. If this were a woman, I'd hit on her... ;D

A PT-19, I believe...

I'm not sure what it is, but there is a whole row of them.

Looking down the line...

Another Spartan...

and another.
