Ginny, if it bothers you that others know what's on your Kindle, how about this:
I recently received an email from a retailer, advertising a sale. I briefly looked at their merchandise (through the email), but chose not to purchase anything. A day or two later I received a second email from them, saying that they saw that I'd looked at their merchandise but didn't purchase. Then they asked me why I wasn't buying from them!! I can understand why they'd want to know, but it did strike me as pushy!!