a decoy
pretty well explained
here's a vague explanation of how it works:
a few top tier "in the know" masons are what some people might call "esoteric jews". they believe stringently in the old testament, and see the new one as an abomination.
All the way up, masons have oaths that involve them being murdered/gang stalked/ maybe worse as penalties for breaking.
The majority are just bored and want a more fulfilling social life or something to belong to. This doesn't excuse the majority of them being easy to be unwelcoming with, however, although I guess this depends on your opinions of secret oaths and all that.
Anyway, most of them are lost christian men who are more or less useful idiots. See, most of the lodges begin with base-stripping the mind and piling more and more pressure to depersonalize the newcomers. The less conscientious ones rise higher quicker and plenty of them eventually become dissenters.
Like any group, we can't exactly claim they're all bad with any responsibility left. We can, however, analyze things in such a way that we can conclude some groups are worse based on the basic principals they promote and the real circumstances that result based on their actions. Because of this, it's easy to determine that masons very obviously should be scrutinized, even at the base levels.