How are the ads that local grocers and restaurants mail to me telling me of sales or giving me coupons which let me get things I'd be buying anyway for less money poisonous?
I would normally get those at the store I normally buy that kind of thing when I'm there to get other things. E.g., most groceries come from the big Walmart Supercenter near my house. If I get a flyer in the mail from the Safeway that is on the other side of town, and see they have a good sale price on one of those things, I might stop by that Safeway when I'm in that part of town on other business and get it.