If you Google "European Labour Only" Australia you will find your answer. Basically the stamps date to the beginning of the 20th century, when Chinese furniture factories in Australia were seen as "sweat shops" paying low wages with which local "Australian" manufacturers could not compete (although this probably not true see - http://www.chia.chinesemuseum.com.au/biogs/CH00016b.htm
Chinese labourers had turned to furniture making when the gold fields ran out, and dominated the cheaper end of the furniture spectrum, especially in Melbourne.
Some states required Chinese manufactured furniture to have Chinese made stamps, which apparently backfired as it made it easier for buyers to identify the well made but inexpensive furniture. There were specific rules which governed the use of a European Labour Only stamp - during the tough times of the Depression and after WW2 it was a way of identifying Australian made furniture - an early call to "Buy Australian". Anyway there are numerous articles which will explain it better than I can.
http://blogs.slq.qld.gov.au/jol/2011/09/25/beneath-the-veneer-september-out-of-the-port/
