Great read this!

If you run a loyalty program, here are some really great tips. 

Firstly, your offering should be "shareable" on social media. No one will take a picture of a free night, put it that way. 

Secondly, millenials prefer experiences (watching a top notch chef) than free stuff. 

Lastly, and the one I like best is that you need to freshen up your loyalty program. There comes a point where customers come to expect "free" stuff after a while - at that point the program has no impact on buying decisions.