Look, I find the uniform a bit of a pain in the nexk at times myself. Before we go offering more concessions if they let us wear business casual lets consider a few things. Anybody with any military experience, or law enforcement experience will be the first to tell you about command presence and the instant increase in authority it provides when dealing with non-uniformed personnel. That being said, putting a uniform on an idiot does not improve things, it does however provide a higher starting point from which to command respect, and excercise command authority with little or no objection.
Starting into a situation in a polo shirt and dockers does not provide ANY advantage whatsoever.
Our uniform sets us apart from the pax, the gate agents, the bag handlers, and even the managers. Anybody can run a ticket counter, anybody can throw a bag into a cargo hold, a rip the zippers off, and anybody can go to college and get an MBA.... very very very few in this world progress to holding an ATP certificate flying transport category aircraft.

Do we belong in uniform; YES !

PS - the crappy uniforms showing up lately from places like VirginAmerica, jetBlue, the gone but not forgotten Skybus and places like that do nothing for our profession.