"I would be upset if I were the parents simply because it was done, as was the wedding, with nothing being said. If he had gone to his parents and said "Listen, I need to do this for my career. It doesn't change who I am inside, but this will help me." Instead, they are finding out everything via FB. But yet, while he can't tell them about names and weddings, he sure can put his hand out for them to supply the basic needs for HIS child."
I can see this happening in the case of an estrangement. For example, what if he's been catching flak for quite some time over all and sundry, so he decides that it's easier just to leave them in the dark than fight it out twice. Then it comes down to needing money, and so he decides to take his hat in his hand and deal with the fallout to ask them for help.
I definitely doubt that he's a shining white innocent party in all this, but I'm left to wonder whether the background that we didn't get would shed light on why he's so reluctant to share his life plans with his family. There's a hint of it in mom not giving him anything from her downsizing because "it's for Brother Smith and he's decided he doesn't want to be that person." I know I'd avoid sharing a name change if I knew my family would decide that it meant I was no longer a member of the family. There's another from missmarie saying he hasn't announced their wedding to any of them one sentence after saying that he announced it on Facebook, because "I really don't like Facebook and absolutely can't stand when people use it to announce things they should be calling close family about first." If the family considered that I didn't tell them because they disagreed with my method for telling them, I know I wouldn't be jumping at the chance to share much with them at all.
These two things don't particularly endear me to missmarie's side of the story, and in the brother's position I could certainly imagine how I would be hesitant to share stuff that I knew would draw fire.