MMM/ERE [1][2] are not about maximizing money at all. They are about obtaining only a sufficient level of capital, so that they are no longer obligated to work for income to continue living happily. The numerical value of "sufficient" gets lower as your expenses decrease.
>I'd think people would be better off maximizing their total happiness.
Based on your comments, to you, happiness comes from experiences which require money, which is perfectly fine. Therefore, MMM and ERE are not for you, which again is perfectly fine.
For others who find happiness in experiences requiring little to no funds, MMM/ERE is an exceptional strategy. I would love to spend my days coding, studying chess, reading books, cooking, mentoring youth, and spending time with the small group of people I am close with (I'm rather introverted).
I knew a guy who wanted to get into freelancing but wouldn't do it because his expenses were too high.
There's happiness, but there's also planning and self control.
I think many people in this thread need to consider if that really is the game they want to be playing. I'd think people would be better off maximizing their total happiness. There's research showing that having good memories from the past positively affects momentary happiness in the present [1]. With that in mind, it seems like spending money on great experiences now is a good idea, while excessive saving could be counter productive.
[1]: http://www.wjh.harvard.edu/~dtg/DUNN%20GILBERT%20&%20WILSON%...