This is called 'proprietary design' - where a company makes something that can only be worked on with tools the same company manufactures. Shimano was screaming, bloody, guilty of this in the early 1980's. They were booed (and pelted with objects) at a trade-show in Los Angeles in '82-3 as bike-mechanics/shops had to shell out around $400/year for tools to work on Shimano's latest gruppo.
This behavior, though limited, continues unabated today. Point in case: The new Ultegra Hollowtech II cranks require a Shimano wrench to tighten the cap on the left side crank-arm. Campagnolo does similar. Take my Campy dust-cap wrench for Record pedals in the 1980's as an example.