The .tel TLD was established for the purpose of publishing contact/location and other meta info at the DNS level, but it hasn't yet caught on unfortunately.
The lack of success of .tel is largely because Telnic has implemented the TLD in such a way that it can only be used to publish contact information - every .tel domain must have its nameservers set to Telnic's DNS servers, which in turn will only serve records pointing to Telnic's web servers, which will only serve pages listing contact information.
You're right, but had it not been so restrictive would people have used it for its core purpose? There are a bunch of other reasons it hasn't caught on. But at this stage I think their best move would be to ask ICANN whether they can liberalise the extension.. I imagine the community would back it.