In baseball, why should there be an unlimited amount of innings if there's a tie?

In baseball there is 9 innings in a game. Its ridiculous to have the game keep going on all night if there is a tie. Why do they have such a rule? Wouldn't be better if after the 9th inning if there is a tie, the game ends or they get just 1 more inning and call it a night? Why waste all this time with all these extra innings? Its stupid