A Blaster's one and only job is to kill everything before anybody else can get in danger, from thirty yards. It's their job, their one and only purpose. And if a Blaster is doing that, they're doing their job right.
It's like when I play as a Scrapper in a team, I basically run on in with a Blaster behind me. Because the Scrapper is SUPPOSED to run in and pray. If I didn't do that, once again I wouldn't be doing my job.