I'm sure you're right about no one expecting people to actually wear the stuff that appears on catwalks, but surely the main intention of the designer is to attract customers. Sometimes it seems the basic plot has got lost somewhere.
I also agree with Jock Scot, it is hard to beat the original, however it is also not a good idea to wear a traditional kilt in a dirty working environment, unless you have enough kilts and money to keep the dry cleaners fully employed, so I can see the attraction in trying to devise practical working kilts and also ones suitable for warmer climes than Scotland.