I'm not really sure if the gov't has anything to do with this (not sure, not saying it doesn't). It seems like usually when i replace a resistor end, it is a 1K resistor, and we do everything "by the book" so I'm sure it's the correct end. I do know there are other resistances, as you mentioned 5K, I think the 5K is a different outside profile, usually found on the older V8's (116/117 for example)with the "W" first spark plug number, and uses the larger spark plug socket to remove them. The smaller end I believe is the one which is 1K and is used on "H" type spark plug which uses the smaller spark plug socket, such as the 102/103 motor. I have the most experience in needing to replace 103 engine wire ends, the ends seem more likely than other engines to seize to the sparkplug, which ends up needing to be destroyed to remove, then the end is ruined to get it apart.
The need to somehow suppress RMI (radio magnetic interference) is a mutual kind of thing, as the offending vehicle with non-suppressed secondary wiring will be receiving just as much interference (zot zot zot zot) on his radio as the other vehicles around him.
It rarely occurs that anyone ends up with a non-suppressed secondary ignition. As Marc has found out, you have to really try to find non-resistor plugs these days.