I've been a woodworker longer than I've been a beekeeper. I was on the board of directors of the No. TX Woodworker's Assoc. for several years, and was president for 3. Some people scoff at biscuits, but with waterproof glue they turn a butt joint into a strong joint that will last many years. The finger joint is traditional, but really is a bit of overkill. It comes from the days when there were no truly waterproof glues available so the joint had to hold the wood almost by itself. A nail was added to keep it from pulling apart, but the joint itself kept the hive from flexing.
I use pine for my hives because it is cheap and will last fine as long as it's painted everywhere the sun shines. For flat wood I use 2 or 3 biscuits per joint to make sure the ends will be held down tight, but most pine is somewhat warped. On warped wood I join the wood so that a single biscuit at the center will hold the cup flat, ensuring a tight joint all along the corner. It has to be clamped until the glue is set, but that joint isn't going to break anytime soon. The joint is rigid and will stay that way until the wood itself fails. I usually put some nails in the joint too, but mostly because I love :) shooting nails with my air-powered nailgun.
Any wood will rot if it is regularly wet or exposed to UV, regardless of the kind of joint you use, although some woods are fairly tolerant of those damaging factors - notably cedar, beau d'arc (aka osage orange), and cypress. Those woods will last longer than hives made from other woods. But even so, regular painting of the exposed surfaces will make a bigger difference in how long the hive lasts than the kind of joint you use. Stain will prevent water damage, but gives relatively little UV protection, so that's why paint is best.
Meanwhile, you can joint a truckful of hives with biscuits in the time it takes to cut a very few hives with finger joints, and you have the same result. As Michael said, with finger joints you are cutting away 3 linear inches of lumber per hive to make the joints. That wood all goes into sawdust. With a biscuited butt joint you only turn a tiny amount of wood into sawdust. And that's a good thing!
BTW, cedar is not favored for bees because it is reputed to be insect repellant, but I am currently trying to remove a feral colony that chose a cavity in a live cedar tree for their home. The bees don't seem to mind the cedar at all, and I don't think they would mind a hive made from it either. They'd soon have it propolized anyway.