How is this okay?

The sitting president of the United States held a "private event" - which we know because it was made clear that he was acting as a private citizen and not in an official capacity, so that he would not have to reveal who was in attendance. 

First of all, that's an absurd thing to say. Everything he does is somewhat public. And because there were people from other countries in attendance then this should be classified as a state function. 

Second, the event itself is problematic. It was all about his own crypto currency. The invitees were his "biggest investors."  This raises many questions about them exchanging money for access to him. This violates the emoluments clause, which I remind you says

"No Title of Nobility shall be granted by the United States: And no Person holding any Office of Profit or Trust under them, shall, without the Consent of the Congress, accept of any present, Emolument, Office, or Title, of any kind whatever, from any King, Prince, or foreign State."

I'm sure that someone - perhaps the DOJ - will try and tell us some loophole. But are we honestly expected to believe that a group of foreign nationals came to this country, invested in his crypto nonsense, and didn't ask - or won't ask in the future - for something in return in his official capacity?

It's another in a long string of him ignoring the constitution, and you turning a blind eye. 

The obvious question that remains is: what are you going to do about it?