I believe that in your real life, they don't.

In the bigger picture functional programming has made huge inroads. Facebook has a Haskell team whose product handles up to 1 million requests per second, and it's also in production at AT&T, Microsoft, Google, Barclays, New York Times and many smaller outfits. The other day I read about a Haskell-like language being used for high-speed, low-latency trading for a hedge fund.

But there are probably at least 100x more SQL developers out there.

Yea because almost all databases use SQL, and zillions of businesses use databases. FP is only a tiny subset of industry coding, but popular in academia and high profile companies.

Because research teams at huge tech companies totally represent the "real life" of normal companies.

There are by far more small companies using Haskell & FP than large ones. I mentioned large companies because they are recognizable. So what is your point?

That's because functional programmers are living the dream.