A good social infrastructure includes affordable housing - a good social infrastructure is one of the bedrock foundations of a growing competitive economy. Also with cheaper overall accommodation costs there is more money to invest in things that can result in very strong economic growth, such as R&D spending and more money to invest as venture capital. (The alternative is an Australia with comparatively extremely expensive housing that has to rely mainly on mineral commodities sales and the vagaries of the education and tourism industries for its wealth). And of course building more social housing will help keep the building industry chugging along.
