I always thought these sorts of things needed five members. You need five people to start a religion, five people for a conspiracy, five people for an orgy.

In Portland Oregon (most strip clubs per capita in the country) it is traditional to use $2 bills instead of singles. It is extremely common to see two dollar bills in Oregon, I would bet a majority of two’s in circulation stay in the PNW.

I was familiar with its use referring to baseheads, and later took it to mean based in facts. https://www.dictionary.com/e/slang/based/