Copyright infringement is a civil affair

Why should reducing a company's potential profit by an infinitesimal amount result in taxpayer-funded jail time? Is jailing you likely to reduce the future probability of your reoffending? (No.) Is the crime so heinous that you should be kept off the streets lest you threaten the public with your foul crime again? (No.) Is the crime so hideous (like e.g. littering, or breathing loudly) that the Daily Mail is calling for the imprisonment of all dangerous scum who do it in order that the little childrun not be threatened and society get its vengeance jollies? (No, and there are damn few things you can say *that* about.)

Doesn't seem like a crime worthy of imprisonment, or indeed being a crime at all, to me.