And there are a lot more.
It isn't easy to start a new shell provider. I'm idling on the help channel of skanshells there are a lot of problems and one of the problems is ddos attacks and that sort [censored].
Data centres which handle DDoS attacks will be very expensive - especially the traffic. So if some scriptkiddies attack your hosts for several hours and you don't realise it - maybe becaue you're sleeping or not at home / in your office - there might be a bad surprise..