They're just angry because sometimes people in Congress spend money on things they don't like in places they've never been to to serve constituencies they're not part of. And they look at the $4/month or whatever that that costs and they would rather have the extra cup of coffee than see bags of food go to Africa or Gaza.
IF they wanted to spend $4 for food to Africa, they can voluntarily do that. The unique feature of government is that you can compel someone else to do it that doesn't agree.