Most ships that fire projectile weapons fire missiles, not torpedoes. To be specific they are called Concussion Missiles. These are the more common physical projectiles fired from ships if we ignore blaster bolts. Many ships, like X-wings, carry Proton Torpedo Launchers, and a handful of preloaded Proton Torpedoes.
These are used against particularly valuable and shielded targets, such as the bridge of a Star Destroyer, the exhaust port of the first Death Star, or the Reactor of the second Death Star. Proton Torpedoes are especially dangerous in ship-to-ship combat.
So it makes sense that Jedi would be trying to minimize collateral damage, while maximizing damage to the actual target. Thus using missiles but saving Proton Torpedoes as a last resort.
As for Tie fighters, shoes can be refitted with Missile launchers, or Proton Torpedoes as well, it's just often one see's them.