I bet they just had an assortment of really nice egg layers. No matter what you have, they'll be very nice chickens. I have my favorite breeds, like anyone does, but to me, they're a little like dogs. I really like all of them!
If you want to, you can look at chick pictures over at...
Rocks, Australorps, Orpingtons and Faverolles. All of them are good layers, hardy in our hot summers/cold winters and have great temperaments. Good foragers, too, but calm if they need to be confined to a run.
I'm partial to partridge rocks, but all the varieties (colors) are great. Ours...