Some people think that a Singaporean social escort and a prostitute are the same, but they are not. If they were the same, then you could register a brothel and operate it legally and exactly the same as an escort agency. However, there is a difference.
The layperson may think that they are the same, but they really are not, and they are not even vaguely close legally speaking. One sells sexual services, one sells romantic companionship and nothing sexual. One is illegal to be publicly soliciting customers for it in Singapore, the other is not.
There is more similarity between sugar babies and escorts, although there are still differences. Read my previous article on this topic to find out more.
It is similar to how you can matchmake people in Singapore, but you cannot arrange for forced or arranged marriages.