If you like printing out coupons from the Internet but don’t like for retailers to know too much about you, um, now might be a good time to stop. Coupons sent to cell phones or printed out from sites like Ebates.com or even Facebook can contain info all about who is spending money on what products, how often, and so on and so forth, all in a bid for retailers to better market to consumers.

The New York Times reports on the phenomenon, which involves retailers working with an online advertising agencies who in turn use a company called RevTrax to process data all about consumers using coupons.

For example, if you’re a fan on Facebook of a certain retailer, that company can see your Facebook ID. If you then print out a coupon offered by them, and use it, they can sift through the data and take a look at who you are and combine that with your shopping habits to better sell you that sweet blender you don’t really need.

Companies can also find out, through electronic coupons, what search terms you used to search for the resulting coupon, which better aids them in finding out what works best to get you in the store and buying when they create the coupons.

The NYT is way more eloquent:

Using coupons to link Internet behavior with in-store shopping lets retailers figure out which ad slogans or online product promotions work best, how long someone waits between searching and shopping, even what offers a shopper will respond to or ignore.

For the most part, the coupons track shoppers anonymously, but in the case of sites like Ebates.com, you could search for a discount on lawn mowers, print out a coupon, redeem it later that day and that information would be available to retailers.

“Over time,” says Jonathan Treiber, co-founder of RevTrax, “we’ll be able to do much better profiling around certain I.P. addresses, to say, hey, this I.P. address is showing a proclivity for printing clothing apparel coupons and is really only responding to coupons greater than 20 percent off.”

Scary? Could be. Useful? Perhaps. But maybe I won’t use that coupon for a 24-pack of Twinkies… just in case.

Web Coupons Know Lots ABout You, and They Telling [The New York Times] Thanks to Howard for the tip!

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