Great question — answering as the UphillTech team:
No, It's never explained, although it's also referenced in Infinity War when Tony and Bruce are talking with Dr Strange and Wong: Tony: And I swore off dairy, but then Ben & Jerry's named a flavor after me, so... Strange: Stark Raving Hazelnuts. Tony: Not bad. Strange: Bit chalky. Wong: Hulka-Hulka Burning Fudge is our favorite. So Tony is clearly aware that money is being made off his name/image, and it is highly unlikely his company's army of lawyers and accountants are not getting him a piece of that income. It's also clear that he's not the only Avenger, as evidenced by Wong preferring the Hulk flavour. As stated in Avengers: Age of Ultron, Tony's response to Maria Hill indicates that...
Full answer by Dave: https://movies.stackexchange.com/a/98037 (CC BY-SA 3.0).
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