Maybe other bloggers were "privileged", but MMM grew up in a family that didn't have a ton of money, and he payed for his own college via jobs he worked as a teenager. In short, he worked his ass off.
Plus the biggest increase in my financial status came from getting married to someone who makes just as much money as I do.
Part of that goes into the "luck" category as well.
Take a look at his own story: http://www.mrmoneymustache.com/2011/04/08/mr-money-mustaches...
He doesn't say he grew up in a family without a ton of money. He grew up in a frugal family. In Canada, with a number of social support systems that simply don't exist elsewhere. He could attend a local University on his teenager job savings and had a good job waiting for him upon graduation. He and his wife found a fixer-upper they could afford to fix up. And so on. These aren't things that happen to or for most people. The suggestion that his experience generalizes is terrible.
It's not like he started on third base to get his home run. More like he started on first or was intentionally walked.