People need to remember this is a Europe-wide rule, not some NSPL little bit of craziness.
As you say, the rule is there for a reason - to reward the other team who have been unjustly penalised by playing against one more player than they are legimately entitled to. If a marshal sees the hit strike, it is not a one-4-one - only if the hit is later discovered.
What it does, in a very positive way, is to put more onus on players to be be more self-aware, and to keep an eye on their team mates as well. I think it's a brilliant rule that makes sense, is fair, is logical, and was perfectly delivered on all fields. It was clear that whilst some may disagree, the concensus was in support of it.