The friend who always forgets their wallet isn’t forgetful. They’re consistent.

Once is an accident. Every time is a pattern, and a pattern is a decision somebody has made without ever saying it out loud. They have learned that you will cover it, so the forgetting keeps paying off. Calling it forgetfulness is the polite story that lets the arrangement continue.

You do not have to make a speech about it. Next time, say you are a little short yourself and let the moment sit. Notice too whether there is anyone covering for you in the same quiet way.