Don't do it.

I get turned off by merchants trying to push more on me after I buy from them. If I get marketing stuff from them after I make a purchase, I wonder if they'll be selling my info to other marketing companies or do other things with my information. It sends a red flag.

I prefer to walk into a store, purchase, and leave never to hear from the store again unless I approach them.
Internet merchants should respect that.

__________________
*** Free Tibet ***