Consider the following scenario: An establishment has a loyalty/rewards program in effect. And the program is pretty simple - For every $40 spent, the patron gets a free stick of beef jerky. Some compulsive dude walks in, spends$40 to 'earn' the free jerky. He does & gets a warm, fuzzy glow 'cos he got something for 'free'! Little does our intrepid hero consider that he could've just walked in & bought a stick of beef jerky for $1 if he wanted.
If you're a frequent flier anyhow it(loyalty card) doesn't hurt but don't allow yourself to be duped by this false allure of 'free rewards'.