Because they believe that AI will replace payroll, which is generally a businesses highest expense. The more AI usage, the more likely they can eliminate jobs and give themselves bonuses.
They are excited the way a farmer is excited when his pigs are gorging themselves on grain and getting really, really fat. The farmer is glad to pay for grain because its much cheaper than the money he makes from selling them for meat.
They are giddy because its almost time for payday.