Problem with Blanket Flowers

There's a problem with my Blanket Flowers

that is quite perplexing.

Blanket Flower
(Gaillardia)

I started these plants from seed early this spring.  

They now live in a neglected spot by my air conditioner, 

taking all the abuse that this hot summer has been able to dish out..

..and even thriving.

What's the problem with them, you might ask?

My Blanket Flowers are quite lovely-

but they are supposed to look like this:

the packet that the seeds came in

These are supposed to be Gaillardia 'Burgundy' - completely red Blanket Flowers.  

But I can't tell them apart from the regular red and yellow Blanket flowers that are in my kids' wildflower gardens 

(and there's no way the seeds could have been mixed up).

Gaillardia bud

I don't really mind too much.  I think they're quite pretty, and the red and yellow go quite well with the other plants nearby.

But I do wonder what happened?