1) I like watches. If all my reps were gens they'd be worth well over $100,00. I can't afford $100 k in watches, but can afford a few grand worth of reps.
2) I like the feeling of "getting one over"; if I can have a great quality rep that costs 20% of the original, I win twice. I have the watch I want and the money saved is in my pocket, not some LVMH or Richemont exec's.