Oh, that's a great addition with money, thanks for it! Nomen est omen @doughtaker. :-))
Well, the pursuit for money will only make you lazy when you have a lot of money and you keep watching it, like Dagobert in Ducktales... LOL - It's the extreme exposure to green that slows us down, but that is relaxation, right?
The question of traffic lights is also an interesting one. I guess "green light" as an universal symbol for starting project comes from the traffic lights. Red was an obvious choice there, because it is alerting, it means danger and green was probably chosen because it cannot be mistaken for red.