I thought (wrongly) that even though this forum is self-selecting for retiring early*, I would have expected the general population to have just as high or even a higher desire to quit working if they struck it rich. Since part of the MMM message is valuing hardship and eschewing complainy-pants-ness, I might have expected people here to be a little less disgruntled about work than the average Joe. And given the high percentage of people here with high-paying and relatively cushy jobs, I would have expected the general population at large to be much more willing to ditch their shitty manual labor job working in 100 degree heat, or their soul-crushing office job, if they were offered $10 million.
I think Dr. Doom's and others' explanation is probably the most apt: A lot of people who are not actively seeking FIRE really have not imagined the possibility of not working for a living, and wouldn't particularly know what to do with themselves if granted a sudden, huge windfall.
* I'm starting to question even this lately. It seems the proportion of people on this forum now arguing for FI but not RE has evened out with the full FIRE contingent, mirroring the general population. Those who wanted to continue working used to be kind of outliers here, but now are a giant number. On a "how to retire early" blog. Go figure.