You agree with that practice? Well good for you.
Wouldn't say I "agree" with it, but I don't disagree with it. I'm indifferent to it overall. There's no harm behind it, it's an agreement between two parties and its under no coercion by a government entity, and the "dominant' entity (the studio) certainly has their reasons behind it (not wanting plot details out early, not wanting negative press too early, etc) the submissive entity (the screeners) goes into it willingly knowing the terms of the agreement and consequences of breaking it.
It's harmless. Boo-hoo, I don't get to read what Ebert or the local paper has to say about this movie until Friday. I think I can handle that.