Why don't autistic kids pretend play?

Good question. Typical 1-year-olds feed a doll with a bottle, representing an act from the environment. Even at 3-4 years, kids with autism put the tip of the bottle in any indentation on the doll's body, sensorimotor play. Despite overdeveloped rote memory, they can't "get" concepts- things you can't see or touch-because of their concrete thinking. That's why therapy has to be intensive & repetitive to work.
Autistic kids. They do but the problem is with themselves and their imaginary world. They can't make the same connection with real world and their human associates.