Why do baseball players constantly spit?

Because they dip.

Because they’ve been catching?

Sunflower seeds or dip. How hard is it to figure that out?

That's one of the great things about baseball. Kind of like golf, you can eat seeds or other snacks from your pocket while on the field of play in between plays.

I remember a cell phone falling out of the back pocket of a Pirates player a couple of years ago as he was sliding into third base.

Not many professional sports like that.

force of habit

in hockey, after a game, you go on bench, and there is spit every f'ing place you can imagine.