Are Singaporeans able to do this?

 

These are foreign workers. Besides the construction of HDB flats, MRT lines etc they can also paint tall buildings like the one above. The jobs come with big risks like falling off the gondola etc.

We need these workers because we don't have the expertise or guts to do the job like the above. Yet, these workers are paid less than S$1,000 per month.

Japan convenience stores can't do without foreign workers

In Japan, most convenience stores (Lawson, Family Mart, 7-11 etc) are operating with minimal Japanese staff. Of the 14 staff at one outlet, only one is a native Japanese according to a report. The job often involves long hours and night shifts which is unpopular among the Japanese. The foreign staff are mainly from China, Myanmar, Nepal and other Asian countries.
The foreign staff has been reportedly abused and discriminated by their customers.
For detail report read here