the whole thing was one big grift. They sent out emails to his supporters before and after the televised address asking for donations for the "official wall fund" and in small print it said that the money would go towards his reelection campaign.

Of course it was.
The wall was 'made up' by Roger Stone because he noticed Trump would forget to talk about immigration.
So to have him remember to talk migration during his rumblings they came up with the wall.
It A/B tested pretty well with the crowd as well.
The Democrats seem to forget that they're negotiating with a deranged lunatic who wants to be at the center of attention.
Which is why he's proud of the Trump shutdown. If anything the news is all about Donald Trump again.
Warren's campaign didn't even make a blip on the radar. All the Democrats can do is talk about how they don't plan to fund a wall.
The Trump deadzone is just sucking up all the attention and talking points.
Or as he wrote (or didn't) in his book: "there is no bad publicity, all publicity is good publicity".
Which is probably why he blocked that bipartisan funding bill. Not because it lacks the wall but because he wasn't a part of it.
The media and democrats once again find themselves fighting a battle on Trump's terms. During the lunch he told them that he didn't care about the speech and it wouldn't matter much but aides told him he should do it.
He'll drag this out all the way to the supreme court if he as to unless he gets bored or something else comes up that attracts more cameras.
The reason he turned so many cabinet positions into 'acting' positions is probably because it got so much attention from the press. Did he ever name a new UN ambassador?