HeartyMeatballs. Yes, of course it would have saved everyone's time to have told him,but that is not the point.
I have no problem in complying with their rules however unfathomable they may seem. I wasn't wasting his time, he was wasting mine. I showed him the cash but that wasn't enough for him. Now I'm not sure if it is possible to get 10,000 euros into an ordinary wallet or not, but it was obvious there was nothing like that amount in there.
So what did it acheive. Absolutely nothing, as I suppose the next person he stops with the same problem will be causing an even bigger queue while they count out a couple of thousand pounds in view of other travelers.