Some facts.
40% of kids take school dinners across the UK which includes 17% who are taking school dinners that are free. So if we take out the free dinners (which will distort any element of choice) thats actually 23% of 83% which is between a quarter and a third choosing to take school dinners based on them being a value for money quality option isnt it?
So for betweeen three quarters and two thirds of the kids at school who pay for dinners, school dinners aren't the first choice. Ask yourself why that is.
It could be because kids would rather be playing football than queuing for food. Or it could be because the food aint up to much. Or for various other reasons I cant think of.
Based on my experience of food prepared at a local school I think the quality of the food is a major factor in this astonishingly low take up rate.