While I must appreciate the effort you're making in attempting to humanize and defend fraternities and their members, your assumption that the animosity stems from a lack of knowledge or understanding of the workings of fraternities is, I assure you, mistaken. However, I'll play along:
Why is it that with all of the supposed focus on brotherhood and community, many (if not most) of the fraternities I've encountered in my university days been hotbeds of debauchery, illicit and illegal activity, and general douchebaggery? I don't mean this in a shallow "they pop their collars" kind of way, but in a much more specific "coming back to the dorms at two in the morning drunk of their asses and shouting loudly their desire for an icy-hot patch" kind of way.
If fraternities are supposed to be good organizations, promoting proper behavior, good works, responsibility, and all that good stuff, why are they consistently complicit in both underage drinking and alcohol abuse (even ignoring other drug use)?
Why is it that the vast majority of stories about a death by binge drinking, or about sexual assault/harassment, or about stupid pranks that do nothing but cause other people grief, involve frat boys? Why is it that I only ever hear stories about frat guys taking advantage of drunk girls in both violation of the law and of any kind of ethics?
Why is it that in class the frat boys tend to be the least engaged, least well-read, least thoughtful, and least quiet? Why is it that they can't seem to keep their ignorance and apathy to themselves?
Why is it that most of the traditions of fraternities either involve drinking or misogyny, if not both simultaneously?
Aside from the mainstay arguments of "it's about community and brotherhood", "we try to encourage responsible behavior", "it's traditional", and "you just don't understand/couldn't get into one, so you're jealous", can you provide one single substantive reason to allow them to continue to exist? They don't do anything to help the community (except the occasional fundraiser, usually some sort of drinking party, which could be done just as easily through other humanitarian and civic organizations without the costs of allowing frats to exist).
Oh, finally, would you please let us know:
1. Did you drink underage, or seen others in your frat (or within the premises)??
2. Have you ever done illicit substances in any context, or seen others on your frat's premises?
3. Have you ever hooked up with an intoxicated girl?
4. Do you, or any member of your frat get drunk and miss class?
5. Does your drinking and partying ever interfere with the lives of others who don't engage in such behavior?
If the answer to any of those is "yes", I think you'll have your answers about why people on this site (myself especially) dislike frats and frat boys. If the answer to all of them is "no", then either you have the single, solitary, good fraternity (I doubt it exists), or you're lying through your teeth