McDonald's Polokwane refusing customers to use thier toilets

McDonald's in Polokwane, fuan park near savanna mall refuses to let customers use thier toilets while they allow us to do sit in. This has been going on for over 2 years. The strange thing is, the restaurant is situated with 2 car wash outlets and total fuel station next to it.if water was really thier problem then customers would not go next door to them (fuel station and kfc) to use the toilet. The management is not bothered about it, i guess for them, its 1 less thing to take care of! Sies!