Edit: I misread OP for "in person" instead of "outside of azb".
The only thing I can think of why you shouldn't do an itrader for in person dealing is this:
In person, it may be easier to make sure the deal is acceptable for both parties because, well, you're both there and can review on demand. When shipping cues and paying via a service to one another, things become less regulated and that's where our problems arise that makes some deals go bad. In my opinion, the itrader shows how well someone performs these 'blind' transactions, not how well someone sells a cue out of their car. Deals over the internet require a certain level of integrity/trust. The itrader should display that integrity/trust, not the quantity of deals that the user has been a part of.
Only my opinion.