Pay to use the toilet at International arrivals and departure :(

We recently traveled via International flight from OR Thambo, while visiting the ladies bathroom I was asked for money when leaving the bathroom by the cleaner. On arrival back at International the same story, I was not asked but the tourist in front of me was asked for a donation in her currency. Are the cleaners not getting a fixed salary that they have to ask for a donation or payment? It's very unprofessional as Not in any other airport we visited we were asked to pay the cleaner!!! It reflects again bad on our country :(