“one company chooses to get one anyway”
I would look into why they chose to get one anyway. Companies dont pay for something they dont need. It could be they are adding ingredients that make it an exception to the general rule of “not needing”, or perhaps the manufacturing or bottling process is the cause of a required hechsher, in which case the one they chose is not reliable for you. On the other hand, they might think it “hip” to have a hechsher on the bottle as a marketing ploy to indicate things like “quality” in which case who cares what they put on the bottle label. If this is a serious question, give it the consideration something as serious as kashrus deserves. If you are merely draying a kup then have fun.