If it was while the plague was active (and there must have been people around at some point to have hung the meat, it wasn't rotten enough to have fallen off the hooks), there would be bodies in the streets. Not every corpse had someone to bury it, and fear of catching it meant many were left to rot where they fell, sadly.
I'm actually playing devil's advocate here. I don't think they saw anything more unusual than an isolated village where most people were in church. They didn't 'notice' the church because anyone used to walking around the countryside doesn't really 'notice' those things. Like 'noticing' cows in the fields or trees growing. They've had an experience that, looking back, was weirder than it was when it happened, if you see what I mean.