In reference to 1%ers:
http://en.wikipedia.org/wiki/Outlaw_motorcycle_club#One_percenter
The origin likely is apocryphal but motorcycle gangs in the US really do wear the patches to indicate that they're hard core bikers and not just week-end enthusiast. There's an example on a set of Bandidos colors about halfway down here:
Angels wear colours here too. Your average bikers wear patches (not the back patches, but BC - bike club - affiliation stuff, or MCC - I was one of these. Not angels, not just enthusiasts - biking as a way of life) But over here, a 1%er is
any biker (well okay, maybe not Sunday riders, but you know, bikers. These days we hardly beat up Lambretta riders at all

and allow that maybe they can be part of the 1% too.).
I've been riding Harleys for over twenty five years. I've modeled colors a few times but I'm really more of the week-end enthusiast than a gang member type. I've known a lot of bikers, including those who wore the 1%er patch, and as you say they're generally great people. That doesn't mean they won't bust your skull if you cross them, however. Most people, even guys who run drugs and rob liquor stores, love their mums and take care of their kids. It's quite in line with the topic to note that very few people are completely evil.
Well, yeah, there's a few you wouldn't want to accidentally chat up their girlfriend! And there's some guys that even the angels take care with, and the ones who've been thrown out of the angels...and they have their own sort of rough justice, which I have observed from time to time...(details on request. I kinda agree with two of the occasions, though perhaps a court might have been a better option) But yes, most of them are not evil, just not particularly good either. Kind of...piratical?
The motorcycle population in the US is quite large and very diverse. There are clean-and-sober bike clubs, Christian bike clubs, the Blue Knights (active and retired cops), etc. Yes, the hard-core clubs, who often are engaged in criminal endeavors of one sort or another, often do sponsor toy runs for underprivileged children, food runs to feed the homeless, etc. There's nothing which says that a dude can't give to charity in the morning and fence stolen goods in the afternoon.
Yeah, all sorts over here too. And a really good example of how people can differ within a stereotype.