For the past few months, a mystery has gripped the northern edge of Leichhardt in Sydney's inner west.

Shortly before Christmas, a long-neglected industrial site on Darley Road, just near the City West Link, was transformed into a Dan Murphy's bottle-shop.

But then, after only a couple of months of wine and beer sales, it emerged the government wanted to acquire the bottle-shop for a tunnelling site for the WestConnex motorway.

Surely they would have known? Why did the government, which has been committed to WestConnex for five years, allow a bottle-shop to be built when it knew it would likely soon tear it down?