Yes, that is one valid example, but I can give another equally valid one. Around a thousand people, maybe, were employed during the construction of the mine I work on. Although not all at the same time. Now the mine is working, we have ( at last count) nearly 800 full time employees. All being flown in and out, either 9/5 or 2/1. And the multiplier effect--a significant proportion of those people don't live in Perth. So they have to be flown TO Perth, either from the WA regions (my case) , or from other parts of Australia. And then, some of those who have to join a flight at the capital city of their state, actually do a regional flight within their state to get to the capital city. Do you see what I am getting at?
The projected life of this mine is another 25 years, barring further discoveries within the lease, or available nearby, with extended infrastructure. Oil and gas do not tend to be big direct employers in the production phase, more technology-intensive. But those 30 people need a lot in the way of support industry, particularly if the site is offshore.
The high point of the construction phase may be past, now we will settle into a production phase(but the capex won't stop dead, believe me.)