Some customers want to feel that they have a choice so they go to retailers that sell many brands rather than a brand-only boutique.
The same applies to online shopping.
I've been to a shop to buy a specific Zenith El Primero (Tribute to Charles Vermot) with my wife and came away with a Montblanc Rieussec GMT.
Conversely, I've also been to the same retailer to buy a ABC branded watch but got a Zenith manual wind watch instead!
Regards,
MTF