My personal response is:
There will always be a situation that is worse or where more people died, but that doesn't mean this isn't a very emotional and trying time for many, where the police and people of Boston were desperate to catch a person throwing explosives and shooting magazines of bullets in their city. Telling people to stay home for a few hours does not seem unreasonable in this situation.
Have some decency and respect for the lives lost, and save your opinions for a more appropriate time.