Even without the modern gizmos, Batman's costume has always been practical. He uses the cowl and cape as a mask to hide his identity/strike fear into his enemies. The utility belt is used to store all of his ****. It's simple.
You just look at Batman and there's no explanation needed. I appreciate what Begins did, but I'll never need to know specifics like, "this thing is really a military survival suit!" or "Bruce and Alfred bought thousands of masks and there was a problem with the graphite with one of the batches!".
1. It kills the illusion of Batman (especially in TDK when Brian Douglass somehow has the same exact Begins cowl) 2. the end product doesn't look like what they say it is. That's a floppy, rubber cowl and suit any way you cut it.
Film is a visual medium. I'll always prefer
seeing cool things like Bruce cutting his own batarangs or putting microphones in his bat ears as opposed to Michael Caine and Morgan Freeman expositing the scene about where things come from.