With respect to your point about frequently not receiving the courtesy of a reply, my company actually encourages that rudeness. I work for a large insurance company and probably about once per quarter we are told that we should NOT reply to an email with an "okay" or "thanks," because each email we send costs the company a certain number of pennies. Isn't that nice?
In the company I work for, the people higher up the food chain consider their time too valuable to be wasted responding to our messages. They often respond only after a situation has reached critical mass and then berate us for letting things get out of control. I notice also that they often respond with catch phrases and slogans rather then intelligent comment. Perhaps rude behavior is a method of control for some people in corporations.
LOL! Check out this corporate guru's advice (pay attention, he makes $20k/gig). Here's a testimonial from a satisfied customer:
"I have integrated many of his views and especially the idea of not saying or writing "No problem" or " That wasn't hard to do, it took no time at all"What I now say or write is "That was my pleasure, glad to be of help. I know you will return the favour someday."
T-Jay Critch, HR Advisor - Training
Dell Financial Services