@ Scott - I was going to say the same.. the word 'couture' is so abundantly (and incorrectly) used in label and shop names and the worst part is the ones who use it couldn't be anything further from the actual definition of the word if they tried.
Look up the word Couture in a french dictionary:
1 couture Noun, feminine (a) sewing; seam
Put Filthy Couture in an french to english translator:
Filthy Sewing
Dilligaf Sewings
Juicy Sewings
Now Haute Couture or High Sewing is regulated by the Chambre Syndicale de la Haute Couture
you could argue that Couture can be used as an abbreviation of Haute Couture but thats clearly not what a sportswear label would be insinuating. What they mean the term to say is apparel.