You were invited to sell yourself, and instead of taking that opportunity, you took your toys and went off somewhere else.
Maybe your boss should have known your market rate, the quality and quantity of your work, how important to the company you were, and that you wanted a raise because you felt you were being undervalued. Maybe he should have known you weren't comfortable being challenged and should have avoided it. But maybe he was giving you the opportunity to inform their opinion further, rather than just to give $default_raise. It seems a perfectly reasonable request to me, providing it was not said in a hostile tone. Whatever, given the situation, going 'nevermind' and leaving, rather than communicating was completely the wrong thing to do.
Sometimes, when you've already raised concerns about being underpaid, when you've given it time, especially if you've kept up with what's going on politically in he company and it seems unlikely to change, you just need to go unless you want the same terrible money for the next 10 years.
Maybe his boss just didnt value him or thought he was over paid as it was? Maybe his boss realized he could finally say goodbye without firing the guy. Maybe this guy just proved he wasn't worth it by his own actions? Maybe his boss and company just weren't very bright.
Maybe your boss should have known your market rate, the quality and quantity of your work, how important to the company you were, and that you wanted a raise because you felt you were being undervalued. Maybe he should have known you weren't comfortable being challenged and should have avoided it. But maybe he was giving you the opportunity to inform their opinion further, rather than just to give $default_raise. It seems a perfectly reasonable request to me, providing it was not said in a hostile tone. Whatever, given the situation, going 'nevermind' and leaving, rather than communicating was completely the wrong thing to do.