Perisher has an area set aside for sledding.
No sledding at Thredbo.
Selwyn makes you pay for some kind of pass to toboggan.
You can always pull over by the road on Kosciuszko Rd.
Be aware that you have to park fees inside the national park and you have to carry chains unless you are driving a 4wd.

IMO Perisher is the resort best suited to day trippers who don't ski.