It's fine to punish the millions of Catholics, and thousands of clergy who find such as abhorrent as anyone else, is it? Don't assume that the Catholic church is worse than other institutions for covering things up, Governments, Schools, Companies and clubs all try to cover-up misdeeds for the good of the organisation. Don't forget how many years there have been jokes about vicars and choirboys, Scouts and Public School boys.
You shouldn't assume that all Catholics think the same about liberal values either there many more Western Catholics who are quite happy with the idea of married priests, women priests, gay marriage and so on than don't, but the church has to carry it's entire congregation with it and that takes time, so why disrupt our Sunday worship.
BTW - The church does punish clergy who commit crimes, they send them into seclusion, which is actually worse than being sent to prison, regardless of any civil punishment.