That's because things like the shirts go into the campaign fund, not her personal bank account.
Harris was worth $3.5M in 2018, and around $8M today - I said about twice, but again her net worth is almost entirely in real estate, which has appreciated at that rate across the board.
As for paying for protection, no - nobody in American history has ever overcharged the Secret Service by millions of dollars for hotel rooms, golf carts, food, and so forth like Trump has - and -WE- paid and are still paying every cent of that to line his pockets.