A question about Quiznos Sub

A friend tries to convince my wife to join her to buy a Quiznos Sub. I did
a 
little investigation on web. Surprisingly, found many Quiznos restaurants 
are for sale in Canada, as compared to only a few for Subway. Well, it
seems 
there are many many more Subway's than Quiznos around. I feel something 
wrong, but our friend can't give a reason.

I love the taste of Quiznos, and it's better than Subway for me. From my 
visits to the quiznos nearby, its business looks good. It's a little
pricy, 
I think it's because of the use of unprocessed meat (healthier?). But why
so 
many owners want to sell it?

Thanks.

John