Bees do forage for miles around the hive and there is no telling what they will bring home. If a neighbor misapplies a pesticide (Sevin for example) and the bees drag it back to the hive, you can end up with a large pile of dead bees in front of your hive, and a hive that may collapse.
Raw, unprocessed honey contains enzymes and flavors that are destroyed by heat. It also can contain small amounts of salmanella which is why it shouldn't be fed to humans under one year of age (although there is debate about that, too). Those enzymes are much of what gives honey its healing properties. Raw honey is absolutely the best thing for burns. Most store-bought honey is pasteurized which destroys the enzymes and much of the flavor.
Beekeeping is a great hobby. It is not all that expensive and it is one way to guarantee the quality of your honey.