Cute story: When riding Space Mountain with crutches, I asked the CM at boarding, "Is there a place to leave my crutches?" instead of "Where do I leave my crutches?"
Deadpan, he answered, "No, you just take them with you, and when they fly out of the sled they'll land at the bottom and be waiting for you." Then he laughed and said, "No, I'm just kidding! I'll take them for you." They did the same thing at BTMRR, without the joke.
In boat rides like Pirates and it's a small world, I laid them along the floor at our feet.