meh
1) most of Scarborough is low income
2) if you're moving away from highest income Yonge corridor then Scarborough is farther from higher income areas in Brampton, Vaughan, Mississauga, Etobicoke
3) you don't have all the blue-balled or dissatisfied dudes due to rushed/overpriced services from airport strip clubs in the area
4) you're not going to pick-up many (any?) tourists in Scarborough (unless they're specifically sex tourists maybe)
5) it might be a different market segment but you've got spas by the mile in Scarborough (probably hundreds?)
6) everyone in Markham is Chinese, and a lot of them are FOBs, so they probably go to spas filled with other FOBs in Scarborough/Markham for cultural/language reasons and Perla is easily reached from Markham where most people drive
7) Mississauga/Brampton/Woodbridge are under-serviced spa markets relative to Scarborough anyways
8) if you're moving away from decent transit (read trains), car ownership is actually relatively low in Scarborough (income presumably) relative to a Mississauga
they should stick it within view of airport arrivals in T1 or the union-pearson train and put a 60 foot by 30 foot giant brass rail like sign out front with flashing neon lights on it. better yet, merge with one of the strip clubs and put it right next door or down the hall from the VIP if anyone wants a strip and a massage (of course then they'd be in Mississauga probably)