Obviously this reaction is by unhinged extremists, so it cannot be used as a yardstick for Muslim reaction in general.
In my view, the simple fact is, for many devout Muslims, their faith is woven into their lives in a way which Westerners find hard to understand because they do not experience it in anything like the same way.
Most Christians enjoy their faith in their lives, but it is nowhere near as much of a daily impact as it is for devout Muslims. Their respect and honour of their Prophet is far more deeply felt than the reverence the average Christian experiences. This in turn means that blasphemy against the Prophet is felt very seriously and deeply.
But of course, only a lunatic would respond by shooting people, so this is not a typical response to such a situation.
That again is entirely a personal opinion.