My first impression of the situation described in the summary is it sounds somewhat similar to a web host shutting down a user's account because their site was a magnet for DDoS attacks - a response which would be uncontroversial. Another analogy that comes to mind is the removal of users' comments in a discussion forum, following a legal threats to the site operator.
The fundamental similarity in all three circumstances seems to be the website operator not wanting to deal with a website user's "baggage", as an earlier poster here termed it. But the next question in my mind is what the differences are in the Kickstart case. Notwishtanding the fact that it's "their site, their rules", is there a point at which nature of the "baggage" may be trivial enough to deal with (e.g. a user being targeted by a spammer, rather than a DDoS botnet) that it's fair to criticise the website operator for being too ready to wash their hands of the victim?