There seems to be a faction of people that think it is a good thing i.e. sensei locked me so hard that coudn;t train for a week, what a poweful guy.
I think any time there is an injury there is an example of a problem/mistake. Accidents do happen, as they say, but we should be working hard to eliminate accidents. I agree with your sentiment about people who delight in giving out pain or assume that everyone wants to train in a somewhat rough and tumble way. Individual purposes will vary and people can train how they deem fit, in my opinion, but I like the fact that in the two dojos I've spent any time in I not only was never injured, but I tended to come away with my pre-existing injuries feeling better.