Have to say most of my comments are made without pressing the PTT switch luckily!!!
However, I have got cross when a pilot on GMC doesn't listen, and you call them many times with no response. When you eventually get them they say "Oh sorry, had the radio turned down too low".
I have said "It is a requirement to maintain a listening watch" or so but a bollocking NEVER. If there is a problem I get them either to call the tower or get an airfield OPS vehicle to have a word with the pilot. For outbounds of course there is the "watch this muppet" call to radar!
Basically I have only seen 2 or 3 pilots in my tower in the last 4 years, so perhaps it is a real problem with lack of task appreciation.
Anyway they are all PILLOTS!!