I liked your insight about the persuit of happiness. Did you know there are ads designed specifically to help people feel less guilty after thy made an expensive purchase? (Merdedes does this).

That's quite interesting - not heard of this before. Can you share more information on this?

I seem to remember Cialdini's "Influence" touches on this (it's a great read about persuasion and influence in any case)

Basically we have a strong need and desire to be self-consistent, and so we seek reasons to rationalise our decisions and they don't need to be all that logical as we try really hard to fill in the gaps. Just present a somewhat plausible story, and you can make people substantially happier about their purchase.

A lot of aspirational brand advertising serves to make you willing to spend money on an expensive product, but also to help you justify the purchase to yourself afterwards by continuing to give you reasons why you made the right choice, so that you go tell your friends about your awesome expensive new Mercedes rather than go around telling them the car salesman tricked you into buying a car you can't really afford once you've had a chance to think things through.

On the lower end, those "write 200 words about how much you love X for a chance to win" competitions are based on a similar principle: They don't care one iota what you write; but apart from getting your address for marketing purposes, they also want people to think about positive things to associate their product with, and commit to them in writing - our need to be self-consistent makes us feel better about the product as a result and we become more likely to advocate the brand and be a loyal customer.