You are right...
In your center malaria testing and treatment is free...
Imagine that the whole town comes to you for testing and treatment, free of charge... You think that man power and medical resources would not be depleted?
Nigeria is one of the biggest endemic regions to malaria... No matter how many well meaning individuals pay for treatment, there would always be outliers. And it is sad to say, that's how Nigerians see themselves a lot of times... Because the government has failed her again and again and again.