I agree that staffing is a separate issue. But they could have pre-ordered as someone else said. The children probably wouldn't tolerate a long drawn out session in there so they would have been efficient in helping them finish in a reasonable time
well that is very true. unless of course it's policy to not to do that 
But that's the trouble with sone of these large companies.
they take online and phone pizza orders. good chance though that pre ordering food wouldn't be allowed. 
all these kind if places, they aren't Michelin starred establishments with well trained experienced staff.ita a minimum wage job that between everything being pre prepared/frozen and bought in and the high turnover of staff the chances of people thinking of that or having the knowledge or training to be able to arrange it are slim.
managers aren't always on hand. people go from newbies to deputy managers in short spaces of time etc.
what makes perfect sense and seems logical to people still seems to have huge instructions in the way