Some of the characters' words and actions are pretty goofy, but the one that takes the cake for me is when Heather and Douglas are in the hellish, rusty Otherworld, and Douglas has broken his leg. Heather suggests calling an ambulance. I'm really not sure how she expects that to work out.
The blood in the restroom can be darkly amusing because, since it's the ladies' room, there's an actual non-fatal non-supernatural reason for there to be blood.
In a callback to Silent Hill 2, if the player has a save file from SH2 on the same memory card and examines a certain stopped up toilet in the shopping mall, they get the option to have Heather reach inside to remove the blockage. If you select yes, a cutscene plays. Heather is about to reach in the toilet, but stops short. "This is way too gross." She then turns and looks straight at the player and says "Who would even think of doing something so disgusting?"
Heather's reaction to finding a dead, barbecued dog in a restaurant.
Who the hell would make something like this? Furthermore, who the hell would eat it?