Trump, like most Republican candidates, runs his campaign as a financial scam, bilking his own supporters for as much as he can squeeze from them:

Former President Donald Trump's reelection campaign issued a staggering sum of $122.7 million in refunds to supporters in 2020, giving back nearly 11% of the money it raised, according to an investigative report published by the New York Times on Saturday based on an analysis of Federal Election Commission filings...

"It felt like it was a scam," Russell Blatt told the Times after his family realized that $3,000 had been withdrawn from the account of his brother, Stacy, who was battling cancer and living on less than $1,000 per month.

Forbes