Of course that would only be of use if full tanks on take off
Every commercial company, airline I'm aware of has a system for checking fuel before departure involving arrival fuel, pick up etc - any material discrepancy is investigated ... applies from 747s down. It's not often airliners/most aircraft fill their tanks - some not for years on end. The statistical history of this pre-departure check forms a quality control check on the gauges and burn figures.
Don't know a pilot who wouldn't monitor the time in flight (chrono etc) against fuel whether you're flying a 747 or something smaller.
Turbines are very easy to monitor as fuel flow is very accurate- having said that, I imagine, that it must be a lot more difficult with helicopters when hovering etc etc as opposed to straight line cruise A to B.