There is a reason for not labeling properly in the lab

The first time I encountered such example would be in the common cold room. A stretch of LB antibiotic plates were placed nicely on a rack. At the bottom pasted a note reading, "use at your own risk, plates not labeled as it was meant to".

I scratched my head seeking for a reason. It never took long to figure out that the note was meant for other "unauthorized" users. It is also very likely that this person had been victim of pilfer for a long time and it reached the threshold of being calm to irritation for him/her.

Rule: "Use and let use" means to replace what you took from others and don't be a parasite.

I have adopted this approach (mislabel or unlabel) not long after. That started when I realized that the solutions I prepared not long ago were pilfered and I was left with insufficient amount at the most crucial time of the experiment. It is upsetting, no?