There’s widespread concern that hospitality operators are wilfully under-serving spirits and beer and/or not using correct measuring instruments (jiggers) to take advantage of patrons. Inspectors from the NMI will be carrying out nationwide inspections and fines are hefty.
Not all jiggers are made equal when it comes to accuracy. Look more closely at that round jigger. If you fill it to the top for a full measure, you'll notice a bubble forms. This is called meniscus and that can lead to bars wasting liquor and losing profits...
There is a flaw in using the white plimsoll line marked on the side of a wine glass. While lines make clear cut boundaries on the sports field or in a car park, the same can not be said for wine glasses.
Unlike spirits, there is no (in either the USA, or Australia) legal requirement for what a measure of wine should be, just some guidelines. So the question remains, what is a standard wine measure?