Finland had a similar tax before. At least here the purpose of the tax was to offset the loss of income incurred from (perfectly legal) private copying (i.e. making copies for yourself or your close friends). In this sense our tax did not excuse piracy.
On the other hand one might not agree to offsetting costs from legal copying and use the tax as an excuse for piracy anyway.
Well, if the copying is legal, then noone deserves to be compesated for it, obviously.
Furthermore, I don't even agree with offsetting costs from illegal copying (since there are no provable costs), hence my moral interpretation of the tax.
On the other hand one might not agree to offsetting costs from legal copying and use the tax as an excuse for piracy anyway.