So 1 kid is okay but 2 isnt?

The hotel policies are really getting on my nerves, many hotels in Booking etc. allow you to book a room with 1 kid but as soon as you input the second kid they offer you double the price and 2 rooms - so in what world do you sleep in one room and have your kid sleep in an inteconnecting room, not to mention the price difference? Whoever is running these hotels in booking and elsewhere need to do basic market research, just put in a unfolding sofa and sorted, kids wont mind...