Salary
Average Salary: $48,150
Expected Lifetime Earnings: $2,010,000
The money is so-so to start, but since you're not putting your life in danger, making any incredible discoveries, or healing the sick, you can't really expect to be taking home paychecks with gobs of zeroes. $55,000-$65,000 is the average (source).
Insurance sales, like any sales job, is "highly leverageable." That is, how much harder is it to sell to a guy buying $20,000 a year of insurance vs. a guy buying $2 million a year? Maybe a few more meetings, but it's a hundred times the volume and probably something like that in commish (source).
Top dawg insurance sales guys make millions a year and get all kinds of perks for being able to move such volume—they're the conduit for the insurance companies to make big time money for themselves because the basic tenet of the insurance industry is that, if nothing happens, you win. So the more money out there, with time decaying away and another day passing where nothing happens, the insurance people simply pocket all the money you paid them (net of the commish to the sales guy).