Isn’t that an issue for governments? you think they are breaking the law? Or are other countries, tax havens etc complicit in this? Singapore is often mentioned as a hub for transferring profits how does that work.
how much revenue is spent on aust wages, aust equipment, paid in payroll tax, paid in super, etc etc. from these big projects?
It is an issue for Governments. Singapore has built a lot of wealth by offering incentives including low tax rates to companies that actually do nothing ( or very little) in Singapore. Those companies set up offices creating paper transactions transferring product from one country to another, making royalty payments to places like Mauritius or the Netherland Antilles on brands "owned" in those countries and a myriad of other transactions making sure minimum profits are made in countries with high company tax rates.
These offices employ locals but also expats who buy cars, spend money and use the airport all of which attract high indirect taxes as well as paying local income taxes.
All of this is of course 100% legal
I know this because it's part of what I used to do in an earlier career.
It's why my view has always been that the only way Australia can ensure a decent amount of tax is paid by foreign companies is to have a lower company tax rate which will take the incentive away to pay taxes elsewhere. Sure we have mechanisms like transfer pricing rules, thin capitalisation rules and others but they are largely ineffectual.