Because the pool at our gym has had to be closed for a week because of 'an incident' involving a parent who took their child swimming, despite the fact that they knew s/he had a stomach upset!
Because the child was ill, there have had to be all sorts of cleaning procedures and lab checks.
It must be costing the gym a fortune - we were upset because DP has joined solely to take DS so that he can regain strength and flexibility following 8.5 months of orthopaedic operations.