I was listening to a marketing presentation the other day and learned an interesting fact. As most of you know, Japanese homes are very small so even married couples often go to "love hotels" to make love. Churn was high and customer retention was traditionally very low because most couples like to experiment with all of the interesting features in the variety of hotels. Recently some love hotels started providing rental lockers, which at first sounds a bit counter-intuitive. Married couples found it convenient to store adult toys and other things that they didn't want their children to find in these lockers. These lockers created a relationship between the customer and the hotel and dramatically increased customer retention. Now these lockers are used to store all sorts of "Not Safe For Home" things.
Apparently, lockers in almost any industry are a great way to lower churn.