I don't believe he is going out of his way to criticize.
First of all, the question of retiring is somewhat problematic. Ask the typical person if they could retire right now, what would they do? Doing leisure activities, going on trips, relaxing, etc. can only take one so far. As human beings we need to be productive (no matter how that is defined) for us to lead a healthy life.
I believe the bigger issue is freedom. MMM's approach is very extreme and works for him. I do believe he lives on much more than 25K and works very hard. To him, the work he does might not classify as work. This is freedom for him. He is building a brand and knows how to market his brand.
The big difference I would suggest is that he is absolutely debt-free. American consumerism and lifestyle, to some extent, is driven by credit. Getting a credit card has become a rite of passage.
I like to follow the Dave Ramsey (http://www.daveramsey.com) philosophy (I don't agree with all his advice but most of it is pretty sound). I've just come across Dave over the past year and I find his message and life story inspiring. His message is simple:
1) Get out of debt (goal is to be entirely out of debt - including house). Only acceptable debt is mortgage debt.
2) Cut-up your credit cards (I don't. Having self-control with this is a big part of it)
3) Save 3-6 months emergency fund
4) Invest 15% every year for retirement
5) Save a percentage for Kid's college
5) Buy a house that is within 25-30% of your monthly income
6) Buy cars, boats, etc (ie. toys) that is no more than half of your total income (at most)
7) Invest your money (He's a big believer in mutual funds which I believe ETFs are now a better choice)
8) Most importantly, stay out of debt.
In this way, if you are making 100K a year or more going out for a $200 dinner or a $10K trip is fine since you are out of debt and all the major priorities are covered.
In some sense, MMM's message is the same as Dave's but the difference is that Dave is a multi-millionaire and works just as hard as he did when he wasn't. He has no qualms about going out for dinner and spending $1000 as this puts no dent in his net worth.