I can't think of a reason not to, but I haven't tried it personally. Bunnies do like pumpkin. Mine always get a little piece of my halloween pumpkin this time of year and I buy canned pumpkin and portion it out in ice cube trays for them. They like it at room temperature or frozen on hot days.
Can they have pumpkin seeds? I know rabbits shouldn't have seeds (except for like BOSS) but some people say they can and some say they can't? (The seeds would be a treat) do they need to be cooked or...?
Yes they can have pumpkin seeds as a treat.
I dont believe they have to be cooked but i would advise they be baked for storage reasons alone.
Put them on a cookie sheek and bake at low temps until their 100% dry. They will nees to be mixed/flipped a few times.