They obviously had temporary holdings in the Latin states that were created. But did they gain anything that holds a long term benefit, whether it be cultural, militarily or spiritually?
This is a very loose question and consequently very hard to answer, but yes, they absolutely "gained" a lot from the Crusades. Increased contacts with the Muslim world in the Holy Land allowed for the "rediscovery" of classical texts (which had never been lost at all, but sitting in libraries throughout the Islamic world,) mainly in the areas taken back by Christendom in the course of the Reconquista. (Whether or not you want to consider that a "crusade" per se is an open question, but the project was absolutely influenced by crusader ideology.) By this route were also transmitted algebra, alchemy and (possibly) gunpowder, among all kinds of other nifty stuff.
Much more obviously, the Albigensian crusade of the 13th century dealt a major blow to the "Cathar" heresy (a sort of Christian dualism related to Gnosticism) - a thorn in the side of the medieval Church for centuries. And the northern crusades conducted around the Baltic from the 12th to the 15th centuries succeeded in Christianizing and (largely) Germanizing a huge swathe of land between the Elbe and the edges of Russia, bringing the people of the Baltic into the fold of western Christianity.
My favourite upshot of the Crusades is the decoration of St Mark's Basilica in Venice with statues looted from other Christians.