This seems to be trying to use a sledge hammer to crack a walnut and include fairly major changes to a system that in reality works pretty well and doesn't need them.
Make any cards not returned a no score rather than a 1. If a card is not returned for a genuine reason, such as having gone home with it etc (which has happened) then it makes very little difference. If someone fails to return a card for other reasons, then again, other than that person being a bit of a ****, it actually makes very little difference to anything. The best that they can hope is that it will keep a slightly higher average in the rolling 20. Again in reality, so what? It just means that they end graded at a level where they are not going to do very well.
The rolling 20 counts for nothing in terms of who will actually win a comp/ series working to the above. No way to try and throw in a couple of 1's to drop a grade, and if you are so desperate to show a higher grade on paper, it really only affects that shooter.
The bigger picture of this should be nothing to do with the fact that people are a bit miffed because someone that should really know better in terms of the example they should set didn't hand a card in.
Why look for "big" problems that aren't really there?