Because the rifle uses an in-line stock, the sights have to be raised or you won't be able to get your eye behind them. The in-line stock, aside from being necessary to the design's function, does a lot to mitigate muzzle rise. If the stock had a drop to it, like a traditionally stocked rifle, the sights can be mounted lower, but muzzle rise increases.
The higher sights do not affect accuracy. Failing to keep the rifle level when firing will throw the sights & bore out of vertical alignment, resulting in less than optimal results.