As they do here as well, but convictions and actual sentences are the realm of the courts. Were they part of the over-reach?
Often more of a capacity issue and targetting the ones seen as ringleaders or who have committed the most egregious offences. That and it's easier to catch the slower ones

Rioters walking home doesn't necessarily make them less culpable, and doesn't make the ones who were caught anymore more culpable, or any more deserving of a public handout for their troubles simply by virtue of the fact that they happened to get caught.