Location awareness in instant messaging, how important it is?

I was thinking about the location information or awareness in instant messaging. By location awareness i mean the information about physical location of chatting partners. Is it important or beneficial to know where people are during chatting, how it affects to communication?

Instant messaging client i'm familiar with has some functionality to indicate users location. This is naturally possible by setting status message, but has also automatic functionality to track different locations. For example when logging in to university network, chat client notices change in network and asks to label the current location. Labels can be like "office", "home", "university"
and so on. When logging again to university, given label "At university" can appear automatically to status information.

But is it meaningful to know the location of chat participants? I have noticed for example that when working at home, there is actually less chat messages from colleagues if location is visible. It seems that in this particular case people actually hesitates a bit contacting compared to "Office" -location. Difference is not huge, but clearly noticeable.

In previous case it would actually be better not to publish location to encourage more communication. (or vice versa, "home" -location seems good way to have less interruptions without need to block all messages)

"at Office" -label beside people name communicates that it's actually ok to send message or give a call. If location is set to something else, the first question arising seems to be if it ok to start chat then? "In the train" may give some context for communication, or reason why the answers are taking so long due poor reception. On the other hand when status isset to "busy" it's clear signal that it's not good time for chatting.

So .. My opinion is that in typical work related one to one chat taking place in single time zone visibility of location information is not so hugely important. Location may give some context for communication, but may be also the source for slight confusion.

Do you know IM communication scenarios where it's absolutely good to know the location of chat partner?