EC261 is not a directive, but rather an EU regulation (Fi: asetus). These do not (and cannot) be implemented nationally. So Finnair was found to be in direct violation of EC261, as there is no national implementation.
Also, at least on one Finnair case (that went as far as the Supreme Court and the ECJ), the Finnish Competition and Consumer Authority acted as counsel for a consumer. Therefore, the consumer beared no cost risk of his own. However, in this case, I suspect that the consumer really has had a paid counsel, as I don't think the CCA is allowed to charge legal costs even from the counterparty.