I imagine most people who are attending the concerts aren’t doing it for the charity factor. They are paying to see the artist. It cost $$$$$$$ to put on concerts. Lots of money.
The key factor is this little blurb from the homepage:
All net proceeds from ticket sales (after musical talent, production, promotion and venue expenses) are donated to the Scholarship Fund, aiding greatly in this effort to assist hundreds of families who have lost their loved ones while they were protecting and defending our nation and our freedoms.
I’ve worked many a charity auction that took in lots of money, but netted much less after all of the expenses involved in getting people to attend... dinner, dance, auction expenses, shipping, postage, entertainment, lodging for invited guests and entertainment that may be needed to get your paying guests to attend... Perhaps Debbie has never spent 40 or 80 hours of her time working one of these things.