Can this place put a sign somewhere on their building saying they can't customize so people don't have a 15+ minutes line for nothing?

I think they do have a sign somewhere to the effect of "no substitutions or special orders" im sorry you lost 15 minutes.

Nope. Dick's has a heritage of tradition! Don't mess with my Dick's!!

What did you want customized? They have plain burgers now and sell condiments on the side.

It took them years to add 'plain cheese burger' to the menu so don't hold your breath.