The amount of evidence you presented is overwhelming.
You could always look for “evidence” yourself but I suspect you won’t. “Trump Fundraiser” is a fine search term.
Well, I did look, and I want you to compare the amounts raised by Trump with those raised by Jeb, Hillary, Rubio, or even Cruz.
The media is just so used to calling campaign events "fundraisers" that they say it automatically. Sure, you are literally correct in that there have been events where a fee was collected. But, the amounts involved were pretty small compared to any other candidate. And, the truth is that no one is expecting any favor or political advantage from giving $100 to Trump's campaign.
And, as much as you might be right that money has been donated, Trump is correct that no one is expecting any favors for donating to him.