I'm less scared of the hoster pulling down your site - not the end of the world - then decided to charge you bandwidth fees for all the MS-DOS attacks. The former presumably has no financial impact, the latter, potentially brutal
Hoster is new to me too.
But I get it as a pattern. (If you dine at the party then you are a diner.)
Sure maybe you'll get lucky and they waive it.
But sometimes going down is a feature if you're not a multi m/billion dollar business