The return address
The top one is a scam, tricking people into opening it. How, exactly, does this lead to a sale? Not sure, but since direct marketers keep doing it, I have to guess that it works.
The second one is sort of a scam, but in reverse. That humble return address in Buffalo, NY? The one that looks like junk mail? Yes, it's our check for thousands of dollars in Google ad revenue from the ads on Squidoo. Very easy for a busy person to throw that one in the garbage, no?