It didn't begin with pirates, but certainly, as a daydream theme, pirates featured prominently. So did horses. And a black panther named Scott. (No clue where that one came from.)
I learned daydreaming early. Dad was in the Air Force. When he was given a new assignment, our worldly possessions were packed up into a moving truck, the cats and the kids (usually in precisely that order) were packed up into the car with the itty bitty travel trailer hitched to it. We road tripped it. First from Alaska to Nevada. Then from Nevada to Arkansas were Dad left us with my grandparents while he went to Iceland. We joined him several months later when he found housing. That airplane trip was interminable. The trip back from Iceland - I still get queasy thinking about that one. From the east coast, we drove across the US to Dad's new post in Idaho. None of this counts all of the camping trips, vacations spent driving from hither to yon and back again. Long hours. Strapped into the back seat with nothing at all to do but stare out the window and make up stories in my head.
I was entertaining myself, I thought. But now, looking back, I wonder. Given all I was seeing, all of the places we went, and the new landscapes we experienced, I suspect I was processing - integrating all of that newness into me. Most of my fantasy stories included whatever landscape we were in. My folks were big about stopping at all of the educational sites - the historical markers where some battle had been fought, or where some major first had been accomplished. We read them all. I'd spend the rest of my day imaging what living through that historical event had been like. Daydreaming myself into history - I always survived, though, because I had the best, fastest horse. Naturally. As a result, I may remember far too much about some of those historical sites.
Every place we went, everything we did was fodder for some new story taking place in my head. Daydreaming became critical when I hit puberty. I stopped sleeping. Not entirely, of course, but it took me two to four hours to fall asleep every single night. This lasted for years. I never told anyone because as far as I knew, it was normal. Didn't everyone lie awake at night telling themselves stories in their heads, watching the plot unfold, then erasing it, rescripting it and running it again until it was perfect? Until it made them feel something, anything at all? Yeah. We eventually worked it out that I needed medication, but it took a very long time. In the meantime, daydreams were the only way to survive. Regular life wasn't all peaches and cream. In daydreams I could be anything and anyone I wanted.
By the time I was twelve, the stories rattling around in my head had piled up to the extent that I had to try writing them down. This is where the pirates came into play. So did the black panther. Did you know that pirates will treat a twelve year old heroine with a great deal of respect if her best friend is a melanistic jaguar? It's true.
Daydreams didn't go away as I grew up. I still fall asleep every night running some story through the movie theater in my head. It's never the story I'm working on at the time. (Cause you'll come up with something brilliant and have to get up to write it down, don't you know, so always switch to something other. These should be the stories you only tell yourself - the ones no one else on earth will ever see or hear.)
The point is that I don't think day dreams are optional. For me, at least, they are part and parcel of how I process my world. There's research out to indicate that dreams blunt emotional trauma. I suspect daydreams do, too. They help us try on identities. They guide us through good time and bad. I suspect they keep us sane. Ish.