Wow...words are words, right? I'm not in a frat(ernity) so I'm kinda out of the loop, but I doubt I would think "frat" was offensive, maybe unless it was used in some of the ways it's used here at the University of Arkansas. (where the Greek population is huge compared to the total enrollment). :)
I've never had a good impression of frats (I may be wrong; I just get that from what I've seen and been around), but I think guys getting together to do cool stuff like ride coasters instead of some behavior they're generally associated with is great.
And now the disclaimer: no offense intended to anyone; that stuff above is only my opinion.
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