parasitic battery drain

Above is true, EXCEPT

When measuring current, it's important to NOT overload the meter, because in the current scale you can blow the fuse --if so equipped, or damage the meter if not

It's important to find out whether the current to be measured is withing limits of the meter, and to start on the largest scale setting

Some "lesser" meters only have a 200 ma scale, so this ain't much headroom.