I hope this doesn't come off as too much flack, because you are a smart and reasonable guy (except for your taste in kettle chips), and I think I get what you are trying to say, but it is still racism. The immature idiots and ignorant morons you speak of are demonstrating their racial biases by engaging in reprehensible behavior. Yes it is immature and ignorant, but if there was not underlying racism and/or if these kids were being conscientious in any way, these particular behaviors would not happen.
The "hard core racists" that we see in the movies and have been warned about through history, are not nearly as prevalent as the more subtle stuff or the immature nonsense that can be easily dismissed (although the hardcore stuff sadly still exists). But its that underlying racism, the actions that can be shrugged off as not being intentionally malicious (or are they?), the stuff that we can't quite put our fingers on, that prevent our society from being truly inclusive. It's harder to fight, and sometimes its harder to see.
But it is all emblematic of racism. So when we see these immature idiots, they still need to be called out. They need to be held accountable. Even if the excuse is that it was a "misunderstanding" or "I didn't mean to offend anyone" or "it was just a joke," well it's time for some knowledge and awareness so these jackasses can learn that their racist actions do harm our communities.