Jetstar/Tiger cabin crew would be on around SG$2000/month depending on the type of contract and volume of sales commission. Lowest would be interns and some foreigners who might make around SG$1500 (possibly less). Senior local with good selling ability should be on over $2000.
No way comparable to SQ in terms of pay and conditions. SQ flight attendant is a fairly prestigious job and the standards are very high, as you would expect with a 5* airline.
Low pay doesn't necessarily reflect on the quality of staff, simply put low skilled jobs here pay very poorly and high skilled ones very well. A checkout operator may work sixty hours a week for SG$1500/ month and be quite happy because it's ten times what they could make in their own country.
The work ethic is different to Australia as well, people expect to work hard for a living without the culture of entitlement, ie no dole. There is no weighing up whether you would be better off taking a job or staying home on welfare, government attitude is there is work available for those that want it, those that don't aren't going to be subsidised.
Believe me, the quality of people working but low paid is considerably better than Australias career welfare spongers who wouldn't dream of taking a job.