Car wash disappointment

At 4 pm I went to Olivedale BP but was told they were closed and were not taking more cars. I begged and was told to leave. Went to BP Cedar where I was told that they had reached their target of 50 cars. All I'd like to know is why weren't we told about these limits? I really wasted petrol driving around for an imaginary free car wash. It was a good initiative by Discovery, it's sad that it went awry.