(1)
There are some Singaporeans holding dual citizenships. (I am no kidding, holding two passports).
Hidden loop hole, to go around.
(2)
1. Singapore aviation industry does not favour the locals.
2. CAAS license is good to use in Singapore and Malaysia only.
(3)
In U.S., there are many flying jobs to build hours. Whereas in Singapore, got flying job for you meh?!
(4)
Singaporeans can't wait to get out and you are coming in? Do you know that every year there are many Singaporeans migrated? Singapore Gov't dare not to release the figure.