I think you have a right ti be disappointed. If a merchant advertises on a website they should keep it updated. Although i often call ahead if something seems out of kilter. I imagine ice cream sales plummet after Halloween
Their Facebook says they're open until 8:30. But still they have seasonal hours but the website is a little outdated. I personally wouldn't blame them for closing early if they weren't busy, Prospect is an incredibly small town.
Thanks! Your answer is awaiting moderation.