Maybe it was just some smart-aleck kids who got bored when the batteries in their cell phones ran down. Heck, they couldn't even spell "Heil" right.
This does not mitigate the fact that what they did was a hate crime, which is heinous by nature, regardless of its degree. More important, even, is what we as a community do about it when one is committed.
Civilization and order owe their continued existence to a complex web of mutual agreements, trust and the assumption that we will abide by a certain code in the way we act toward others. If violations of that code are allowed to go unaddressed, the edges of confidence in institutions begin to fray, and--humans being what they are--we are tempted to revert to the tribalism that is our natural state of self-protection.
The stigmatization of hate crimes is one of those places where self-interest and the interest of the whole of society find common cause. This is why organizations such as the Anti-Defamation League are equally vociferous in condemning acts of hatred against Muslim- and African-Americans as they are in condemning those against Jews.
Whenever intolerance toward anyone is tolerated, we all lose something as a community. This principle must be taught to those who don't comprehend it, over and over again.