Government Rates
The 'Craziest" thing the US government has ever done to reduce cost is to set per diem rates for all travel locations, and to quit collecting receipts for meals and incidental expenses (M&IE)! It is the only intuitive move they ever made. The savings in paper-work and man-hours is literally incalculable. And they have stuck with it for many years. How crazy is that?
My wife recently worked for a small company that required the full restaurant receipt for every meal, not just the credit card total, even from senior management. If you don't trust your employees with M&IE, how can you trust them to help run your company?