I had never seen this before. It could be because the episodes were so butchered in syndication.

Pies fly at approx 5:13.

https://www.youtube.com/watch?v=VQXiMwJ8DZQ

Nice! Carol got wet a few times on the show, as well.

I once read somewhere (maybe here?) that Debbie Reynolds had a short lived sitcom during the 60's where she got pied in the face at the end of an episode when she was addressing the audience. I don't know if it's true, but I would love to see it if it is.