It ain't just planes and ships. Have you never seen:
And it goes further than that. As a guitarist I've given a guitar a name...and it wasn't Steve. I think it's because as men we often tend to isolate with our obsessions and we begin to see it as our companion on whatever journey we happen to be on at the time and, statistically, the vast and overwhelming majority of men love women and having them in our lives. Yeah, this is some armchair psychology but that's my take.
I did but... then my daughter informed me that my blue cars (three) have to be boys. The other colors (five) have to be girls. They go out on dates sometimes according to her, especially the pink vorteks and blue granite