It would be helpful to study the hotel program's t&c's to see why the OP feels scamed.
In my opinion, the hotel chain discloses the t&cs on the websites:
http://www.lhw.com/leaders-club
http://jp.lhw.com/leaders-club/membership
But the OP is right by saying it is not mentioned about the two different hotels:
Earn Complimentary Nights:
Earn one complimentary night at any Leading Hotels for every four or five stays completed before your anniversary date.
Leaders Club
Receive special advantages at every Leading Hotel across the globe
A one-category room upgrade*
A unique welcome gift at each Leading Hotel
Earn Complimentary Nights
Member Only Offers
Unlimited
Special Benefits for our Unlimited Members
Guaranteed upgrade at the time of reservation
A Priority Pass™ card which provides access to over 600 VIP lounges in over 100 countries
Complimentary Gift Memberships for Your Family
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