Honoring A Service Man On the Airplane

Our last flight back to the mainland from Hawaii, was from Phoenix to Pittsburg.  Jess and I were not seated next to one another.  The flight was full, so as we boarded, I asked a young man (it’s funny to call someone a young man, he looked to be about 18-19) in a military uniform if he’d be willing to switch seats with me…  

He was in an aisle seat sitting next to Jess and he would have to move to a middle seat in the next row up.  I told him that he didn’t have to say yes, that I was just asking.  He said no problem and moved to the row in front of us.  
As I got settled in my seat, a man stood up and addressed the young man in uniform saying “I’m in an emergency exit row and I’d like you to have my seat.”  (Emergency exit rows have a lot more leg room, and he was giving up an aisle seat.)  The service man, tried to refuse, “no, it’s okay.” And the man insisted.  The service man, stood to his feet and stuck out his hand saying thank you to the man giving up his seat, the man giving up his seat said, “no thank you.”