Found something else, which is probably due to easyrpg.
When I use an item with multiple targets, there are as many units consumed as there are targets.
So if I’m using an item that heals all 4 party members, then 4 units are being consumed.
edit: Not so sure about this anymore. I’ve also had the case that I used an item on a single enemy and lost like 3 units of it or so. So it’s possibly not necessarily because of multi target.
thinking about it, it is probably due to items that have a multi target, but there do not need to be multiple targets around to consume more than 1 unit… ^^