Honey does not go bad, ever. They have literally gotten honey out of the pyramids and sampled it and it was good. It may crystalize over time but it won't go bad. If it's mixed with garbage THAT may go bad but honey will not.
The use by thing is an FDA requirement, all food items has to be labeled. As for yoghurts, cottage cheese, all that stuff. Just because it's past it's date does not mean it is bad. Use your schnoozer and give it the smell test. Ive eaten sour cream months past it's date, it was in a very good fridge tho, like 34 to 35 degrees in there, eggs, a long time. Just be careful on meats. Poultry / Pork will do you very bad if it's got bacteria going. It won't kill you but trust me, you'll wish it did when that sets in your gut. Also as an extra precaution if you are going to be eating meats / stuff that might be a bit past it's prime, make sure it's WELL cooked. If it's cooked properly, while the taste may be off a bit, you will have killed off all the Salmonela and other creepie crawlies that was in it.
Aaron