Congratulations on your good fortune.
"Money Fairy" sounds like the stage name for some particularly sleazy gay porn star...
Has anyone else had the 'money from nowhere' thing happen?
Yeah, I have. But I don't think there's anything too weird/mystical about it.
Thing is, there's a lot of money that can be made and a lot of ways to make it. It's just, most of the time, we can't be bothered to go looking since we have a steady income from one source and budget within that income instead.
Whenever I make a real effort to look for another revenue stream, I can usually find it. Might not be much, and so might not be worth the effort, but it's pretty doable if you have a slightly entreprenurial bent and once you find a successful formula it can last a while. I ended up starting two small businesses as a result of wanting to do a couple of hobbies more frequently so needed to make some money doing them to make it worthwhile. Now, if I wasn't full-time employed as well, I'd be able to expand those business instead. But I am employed, so I can't. But they tick along in the background, generating useful pocket money and when I retire, I'll scale them up instead.
To use another, much smaller, example - your money for market-research. I sometimes get the same sort of offers and tend to turn them down since I can't be bothered to devote the time to doing them. But if one wanted to, there are various organisations you can register with to get paid to do surveys/attend focus groups on a more regular basis. The only one I do is YouGov's surveys, which hardly pay anything at all (generally about 50p-£1 for a few minutes survey time), but I like doing their political opinion polls (I'm an opinionated so-and-so), so for me, it's worth doing.
It boils down the old time=money equation and down to opportunity cost - could you be doing something else with your time that you value more (either financially or otherwise) than the money generated?