it isn't etiquette that's lacking, it's lack of discipline and lack of adherence to regulations stipulating that standard phraseology be used.
I can't generalize, but in the ATC clips from the various countries I've listened to, ATC is usually more professional with the RT. Flying in the US, on occasion the RT is just appalling. I can't tell you how many times I’ve heard pilots say something like "NXXY are-tee" as opposed to using the phonetic alphabet...or how about "contact tower on nineteen twenty five". try "cleared for the loc-d (localiser dme) to the left".
The CVR for the Comair crash in Kentucky has ATC issuing the clearance:
"...cleared for takeoff."
to which the PNF replies:
"cleared for takeoff"
Neither party states the RW designation. Not pointing any fingers at the crash cause here, just citing an example.
I'm not at all saying that my RT is 100% perfect all the time. i get lazy and unprofessional sometimes too, but make an effort to avoid it. ATC sure adheres to the rules better than we do.