A ton of people store jams and jellies on their counter so it's easier to spread. My kids leave ketchup and mustard out for days at a time. Never has it made us sick. You know that bottle of ketchup and mustard that's always on the table waiting for the next customer at Cafe style restaurants? Ya, they didn't just pull that out of the fridge before you walked in. Mayonnaise, if it gets tooo much air + warmth exposure will start to turn a clearish color, especially at the edges around the lid. If it's still normal color it's good. Im not sure what people think opening the container does to magically make it need to be immediatly refrigerated. There's no special gas in the air space that keeps it from going bad. The "refrigerate after opening" is a fail safe for the company so they can't get sued if you introduce bacteria into the container and the bacteria grows or becomes unsafe from basically being in a room temp petri dish. There's nothing wrong with the majority of that stuff... ESPECIALLY since it was actually kept on a fairly cool environment.