*its members.
Does Chess.Com really care about it's members?
You can also go ahead and start your next game, particularly if it is standard (just in case you were wrong and they came back, you wouldn't be materially disadvantaged in finishing them off).

I'd be happy to block them, can anyone tell me how to? But aside from that, if Chess.com cares so much, can someone tell me why such a fellow with such a track record, is consistently allowed to come back and bother someone else?
So you lost two minutes to your life big deal. You lost more time making this post, reading the comments than responding.

To Block: Click on their name, select Block Member.
Or, if they have commented on your profile (or someone else's) you can also click on block member, which should be next to reply to Delete below the comment (I.E. Reply Delete Block )

Chess.com sole purpose is to earn money from it's customers and having fun while doing so, so your argument sounds strange. What do you expect from chess.com, using an agency that bans everyone that has the wrong opinion like the NSA? Also what happens if someone is drunk and makes a few bad comments, should that person be banned from chess.com?? Off course there are guidelines for behavior that will handle the worst but otherwise it's block and let live I suggest.

ICC (Internet chess club) has a very popular option called "nosecape". If you set that flag, you agree that you lose if you disconnect. You can set up a filter if you want and only play others with "nosecape" set.
It is popular because folks like it. You are not forced to set it, but it does provide a very effective way of dealing with this issue.
Is this a serious offence? Clearly not a "hanging offence" -- but the popularity of "noescape" speaks for itself :)
I'm sure many have you have seen similiar behaviour; someone in a losing position just disconnects instead of resigning. You are left waiting for two minutes till the game is declared forfeited.
It happened to me tonight with a fellow named, ggardi2001. Lo and behold, when I went to look at the comments on his profile, it's clear that this is a long standing pattern of behaviour on his part. Which raises the question - why is he still allowed to be a member on chess.com? Why is chess.com happy to take my money for my premium membership, but provides me no way of avoiding people like this in games?