Graffiti as a notion of identity

In response to the former post with the same title as this, the author tends to hold an abohorrent view of graffiti artists. To write that graffiti is "...an identifier of territory similar to that of a dog defecating [on] a pole to signal the boundaries of their territory," is not only a horrific analogy, but, as far as I understand, a complete misunderstanding of what graffiti is and how it came about, as well as the place it holds in society today.
Channeled as a visual aesthetic to represent hip hop culture (this was not always the case, as can be seen in Style Wars where one the artists is wearing a Van Halen t shirt...), graffiti may have represented a notion of identity, however the nature of hip hop as a music and a culture in general has surely redefined this numerous times to a point where to understand identity in relation graffiti is a redundant concept.
Graffiti, like hip hop in general, illicits such a wide range of viewpoints and attitudes from such a wide different audience that to view it as defining a culture detracts from the culture itself. It makes sense to see graffiti as a visual signifier of a movement, or a political statement, since these viewpoints were both intended and make sense when looked at from opposing viewpoints. To analyse graffiti's importance as a notion of importance forces us to consider antagonistic viewpoints toward that culture in order to understand it.
To posit a viewpoint that graffiti bears the stamp of cultural identity implies that graffiti visually represents a movement that seeks to define itself in terms of its opposite, as the oppressed cultural other in relation to dominant cultural product. While this may have been true twenty years when Public Enemy were releasing 'Public Enemy #1' and Kool Moe Dee's How You Like Me Now was breakin loose, we can no longer characterise graffiti as the visual representation of this movement, due to the characters and players who now control the industry, and indeed packaged a movement into an industry. Graffiti is now little more than a font for rap album covers and magazine ads in 'The Source'. If this is identity, then the movement has sold out.
I don't believe this is hte case. hip hop as a movement always revelled in its multiplicity of expression, of which graffiti was only one vehicle. To say a movement can be described by a vehicle is as shallow as saying a man can be defined by his automobile (sadly many of the more marketable members of the hip hop community seek definition of self through their Lexuses, however this a misdirection of the movement).
Graffiti is an expression of a people's identity only to the extent that people choose to you that mode of expression to express an idea that is consistent with a movement. As soon as that movement becomes an industry then that identity can no longer be faithfully replictated by its own manifestations and requires redefinition.