I suspect this is to makes sure that they don't have to comply with High Value Dealer proceedures for anyone taking the floating equivilant of 15,000 euros cash for a single or series of connected payments, technically their limit could be about 10,366 (mid-market rates at 17.02.05 13:18 GMT). HMC&E recommend HVD proceedures for anyone accepting more than 9000 at present. If are able to accept such cash payments then you have to have basically register and appoint a Nominated Officer who you employees have to report such transactions and it is then the NO's role to access the report where appropiate forward it onto NCIS. This involves having to train your staff in anti money laundering procedures and put in place internal reporting proceedures etc which are a pain so it is easier to refuse to take such payments.
To be honest I wouldn't too keen to accept that sort of amount of cash anyway and I can't imagine that their is that larger demand for paying that amount of cash other than laundering money.
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