The interesting part of the article was where they specifically targeted one of their whales. They found out which American football teams he liked and introduced in app items that matched those colors so he would buy them.
Casinos are well known to get as much information about their players as possible, and to get their high rollers to keep coming back.
Retail stores have done the same. (See How target figured out a girl was pregnant [1]).
With technology providing more and more information and indirect insight into our lives, it's only a matter of time until everybody does the same. The only way to prevent it (as best as possible) is simply to not play/not link to facebook/etc.
[1] http://www.forbes.com/sites/kashmirhill/2012/02/16/how-targe...