A car is being pushed until it stops by a hotel. The person pushing it immediately realises that he is bankrupt. Why?

Answer:
He's playing Monopoly

不好意思，看了答案都没懂它的意思。哪位大虾明白的话，请解释一下！ Thx!

car might be one of the playing pieces in the game.
not too sure about the rules though
but i believe to understand the problem, this is where to begin

there's a term in economics called cartel which usually happen in oligopolies

but again oligopoly is not monopoly and in the answer for the puzzle, the "m" is capitalized. so i guess it's still about the board game.