It does seem to go against any semblance of natural justice that a team can be responsible (as in the referee excludes the rider) for an incident that has the end result of a team losing a rider for the rest of the meeting, whilst the team that caused the loss can, after the one race exclusion, keep riding at full strenght.
In league matches I've often thought it unfair that the top rider can only be replaced by a reserve in those circumstances, but better than nothing.
Why not allow them to use rider replacement - with everyone entitled to take one extra ride?