Royal Mail - Junk Mail and Customer Service

So a postman with the Royal Mail has been suspended for telling customers how they can avoid receiving non-addressed junk mail such as adverts and money-off coupons for the local Pizzeria.

Why have they done that? It's a piece of received wisdom that no-one likes receving junk mail, so surely the Postman was just doing a piece of thoughtful customer service?

On the other hand, the Direct Mail industry tells us that this sort of junk mail actually works, and delivers a relatively high take up of offers amongst recipients. We actually use the money-off coupons. So our behaviour as customers would seem to tell a different tale from what we say?

And of course, this form of mail is quite lucrative to the Royal Mail, and subsidises them to keep delivering first class letters for 32p. Without it, the Royal Mail would go down the pan, or letters would be more expensive. Interesting example of customer behaviour and a systems thinking issue.