There are two reasons, primarily. One is what I mentioned before, in that the firearms manufacturing design choices represent a continuum. The firearms will have features that range from hunting to tactical. You can add and subtract individual features on a firearm, and there's no clearly defined point at which the addition of operating characteristics changes the firearm from a tactical firearm to a non-tactical firearm.
The second reason is that the firearms themselves can often be modified to switch from one category to another. They can be equipped with features that are suitable for hunting, and then those features can be added and subtracted in order to produce a tactical firearm. That's the trend today in manufacturing, towards the use of modular firearms that can be transformed from one purpose to another simply by adding or subtracting components.