Fair argument. But from what i learn from singapore. They build their road as a dual function as a temporary runwat and car road. And singapore is not the only one. So they should already think about the logistic support too.
Then you will also know that these roads that also serve as runways are not built somewhere in isolation. They are literally right next to an airbase.
They fulfill 2 functions - one is to provide more resilience to the airbase from runway denial munitions by literally having more runways and the other is to improve sortie generation by having more options for takeoff and recovery of package. As far as the RSAF is concerned, they are not meant to function as a separate sortie generation point.
The idea of having FARPS or lilypads all over to play shell games is kinda fantasy land territory as has been highlighted by many - there is a tremendous logistics tail to even re-fuel/re-arm jets. It's do-able but it's not something you pull off on a whim or at last minute without some form of prep or pre-positioned log.