Power consumption LCD display on digital watch 12h/24h
A single segment of an LCD display can be modeled by a (very tiny) capacitor. The segment is ON when there is a voltage difference between the capacitors terminals.
The LCD gets damaged if the segments/capacitors are driven with a DC voltage. That's why the LCD driver always needs to toggle the signal polarity on both terminals. (Check the mean voltage in the graph above: It's 0V).
For driving the segment in ON state, the capacitor is recharged a lot (switching losses!), where in the OFF state, there is no voltage difference between Backplane and Segment terminals.
So your assumption is right: The fewer segment are in the ON state, the less current is used.