Do recommendation algorithms not take this into account already? Perhaps privacy policies make it harder to automate this effectively.
The perfect Netflix customer is one always on the cusp of cancelling from lack of use but never actually does ...
It still chuckles me up when they send me an e-mail once in a while, about what I might like based my past viewing preferences.
Note: My GF, has a profile that she uses sometimes, but mine haven't been used since the account was created.