What is with all the illegal machinegun threads?
It is the machineguns that are illegal, not the threads.
One can ask all kinds of questions anywhere (and especially behind the anonymity of the internet, as rjrivero pointed out, without fear of prosecution or even very much scrutiny. This is supposed to be a good thing.
As far as people implying that they may or may not have committed or be committing a criminal act. That may or may not be the intended message of the post. I have seen enough poorly written (and authored a few myself) posts that leave a great deal of doubt as to what the author intended. That is, I may write that I have a gallon of some illegal substance, where what I intended was that I have an empty container with suspicious markings on it.
Sometimes you gotta read between the lines, and sometimes you get it wrong. And sometimes the people posting are just yankin' yer chain.
I don't know. Human nature being what it is, people tend to push whatever envelope they are in. I, for one, am glad that our moderators on TFL allow a wide latitude.
It is irritating to see yahoos yammer on about their this or that, but the alternative is to allow other yahoos (no slight to our moderators is intended here, just symmetry in my rhetoric) to put muzzles on us.
Go onto CraigsList and try to post a "Wanted" or "For Sale" post for a firearms-related item. Even telescopic sights are specifically named as forbidden in the Craigslist rules.
To paraphrase William Blackstone, "It is better to let 10 criminals post on TFL than to lock out one with something worthwhile to say".
Besides, if we let the criminals post on, it might make them easier to catch.