I think you answered you're own question asbestos.
Price point. The mfgrs want their tools to hit certain price points in the market. People who aren't going to use the tools for their livelyhood, don't want to pay that much. They do want quality tools that will last (at least many do). As a homeowner, I will likely use a particular tool say a couple times a month. At that, probably have to recharge batteries each time after I use it. That means roughly 25 charges per year, so 4 years before reaching the "magic" 100 times. Now as a homeowner just using the tool infrequently, I can probably live with the now degrading battery performance for a while longer, so I could go a good five years without needing a replacement.
Of course then there are those who NEED to have the latest greatest newest most techno-rific TOYS that are available and don't care about the price.