Spitting and Urinating Not as Bad as Littering

Mum: I don't get it, why littering has a heavier fine?
Jackie: Because littering will make Singapore look ugly, but for urinating and spitting, you can't see it, so less fine.
Mum: What?
Jerrie: Because, you have to hire cleaners to clean the litter. You can't see urine and spit, so no need to hire cleaners.
Mum: What??
Jason: Those who urinate in public are mostly kids.
Mum: And those who spit are probably the coughing old folks? So, these people have concession?
Jason: Hahaha