Well, for my FC we also have a ls too which we prefer to use as a number of our friends are in other FCs, so we use the ls to keep in contact with everyone. The FC chat channel seems to only be used sparingly for more 'FC orientated' discussion.

That and force of habit from playing FFXI for over a decade has ensured I just type '/l' automatically now when I want to speak to people without even thinking about it.