In certain parts of the EU there are restrictions on merchants accepting cash for transactions over a certain amount.
It was my understanding (perhaps incorrect?) that these laws prohibited even private party cash transactions, not just merchant transactions.
Assuming correct (if not, wait a little while and it probably will be), this same law could likely apply to anonymous virtual coin transactions between private parties.
in germany private cash transfer are unlimited. most private car trades are made in cash (reasoning is if the seller claims insolvency he keeps the car and the money - with cash its not possible)
BUT:
- many companies have limits (e.g. "Deutsche Post" 2500)
- you have to explain yourself to your bank when depositing (i even had to explain myself once when i sold gold (directly at my bank) for just(!) 500)
but i think you are right that cash will be more restricted.