Because money talks. I used to play a game when I really wanted to bargain hard on something: I'd change my money to as many notes of the lowest possible denomination, and show up with a huge stack of notes.

You're be surprised what a huge stack of notes can do. It triggers something in the recipient of said huge stack of notes. It's deeply psychological. People stop thinking when faced with a huge wad of money.

People will do anything for money, including bad longterm decisions.