It drags you down though. Every supermarket you go to asks for your loyalty card - which I refused to opt-in to for years, but you still are confronted with the question everytime - it gets tiresome.
I do my shopping by proxy, through a partners' loyalty card, and I've been pretty surprised at how sophisticated these systems have become.
There's a desperate battle between outlets now for custom. Loyalty cards now lead to offers (coupons) on items from the weekly shop, and our shopping basket is quite anormal I'd say. We are actually recouping some worthwhile savings, for once. Rather than being offered some promotional discount on something I have no interest in. I feel a little wrong about it, but I no longer can resist the enticement.
Ted Billson. There...use that. His email address is ted@bill.com if you get asked. ;)
Another 'fuck you money' project: a set of domains with an open SMTP server that does nothing but flip the headers around and re-send the message back to the sender.
I've been asked and politely declined probably hundreds of times by now. It's never led to any further interaction beyond my simply smiling and saying "no thank you".
The cashiers don't question it, or stare, or even miss a beat. (sometimes a 'new' person will hesitate for a second; thrown off their muscle memory pattern). But surely they hear it from more people than just me.
And I find making a shopping list beforehand, based on what I've actually used since the last trip, is more effective than coupons or loyalty cards. The coupons did start getting more properly-targeted, but they also entice purchases I hadn't previously had on my list. Which calls into question the notion of having 'saved' any money.
Similarly when I would be 'saving' money on things that are only useful when I purchase its non-special-/non-coupon-priced complements (e.g. a coupon for hotdogs leading to a purchase of regular priced buns; or a coupon for peanut butter leading to a purchase of regular-priced jelly).
(Or alternatively "abuse@localhost"? "root@127.0.0.1"? "spam@gmail.com"?)