Yes, you are not the only one who discards marketing materials received in the mail. Traditionally, marketers are satisfied with a 3-5% response rate with direct mail. I'm sure the response rate will be higher, if they slap humor on the postage stamp.
I recently found a link on a friend's facebook profile and completed the survey, "How many five year olds can you take on in a fight?" Normally, my patience runs thin after 4-5 questions on a survey, but I completed the 13 humorous questions. ...And the results were stunning, apparently I can take on 23 five-year olds in a fight.
What's this have to do with marketing? Well, the site was designed by Oneplusyou, an online dating website. ...I really didn't know that five-year olds were allowed to date, but I guess times have changed and so have the rules of marketing. No, the survey may not lead to direct sales or new registrants, but it is creating traffic ...and lots of it.
The survey illustrates how online humor can create substantial awareness and knowledge for any company without the expense of a single postage stamp, even if the quirky marketing idea does not directly relate to the product.