Buying companies up isn't always the best option, neither is buying up patents.
1. Buying a company almost always removes the traits that made that company productive in the first place. This company was innovative enough to get these precise gyroscopes cheap enough to put in game controllers.
2. When you limit production (by being the only user) you are not maximizing efficiency, if others use the technology (whether in gaming or industry) then the prices will be kept low. Development and production costs tend to be higher for monopolies than for large competitive operations.
3. Even if you own the patent, there are many methods to get the same results. This isn't the first Gyroscope sensor for a control mechanism, it's just the most efficient production method used. It's 100% guaranteed that some one will come along and find a way to make this tech even cheaper using a different method.