In my experience, Purdy will only use this "marketing-related information" for a scant few email and/or snail mail Purdy promotions.
A couple of years ago, I signed up for Purdy's beta testing program for new products. Got a few of the early prototypes of their new Chinex brushes to play with, among other small hand tools - but I never did get a single piece of mail from them... so unless they've changed their strategy drastically, I'd expect they won't bombard us with unsolicited mail. No guarantees, though...