This is a commonly-heard argument against anonymity. It is based on several false assumptions...
Article taken from Issue 2 of The Ox-Fly - Oxford's radical newsletter:
http://oxfly.theoarc.org.uk
* Second assumption: that breaking the law is always wrong. Actually, laws are made to suit the ruling class, and don't always fit with most people's ideas of right and wrong. For instance, stealing food when you are hungry is illegal, but stealing the profit from someone else's hard work is called 'employment'. Punching someone on the street is illegal, but dropping bombs on people in foreign countries is fine. Smashing factories that produce those weapons is a crime, but evicting a family from their home is legal. Meanwhile new laws aimed at animal rights activists have seen people imprisoned just for going on routine non-violent demos.
There is no shame in protecting yourself from ending up on a database. Masking up is one way to fight back against dirty police tactics, and protect each other. If people all look alike, no-one can be made into a scapegoat. This is often seen as an anarchist thing, but not all anarchists mask up and not everyone in a mask is an anarchist!
For more info and details of how to stay anonymous, see tiny.cc/maskup