But what is the cost base ? I'm guessing PLN 30 for heat and light, PLN 10 for showers and lets say PLN 30 inc ZUS to have a janitor open it up and stay on site for 1,5 hours.
Heat and light shouldn't be 30PLN in a new school. Showers? No need to use them. As for the janitor - they're normally there anyway for other things, and very often, they're often retired people working part time anyway - and so, cost very little. And also - this 100PLN is during school hours.
There's no way that it costs a school 100PLN an hour to actually rent a hall. And we don't mention how schools will rent entire classrooms at a very low price to 'friends'. Or in Poznan, how several school directors took kickbacks from a certain language school ;)
As for the school not being worried about poor kids - if they actually believed in education, they'd be hiring the place at cost price.