for me the most important thing whenever you wear the armor, planned event or not, is to maintain a proper code of conduct.
Walking down the street really blows people away and brings a unique Star Wars experience to an otherwise uneventful day.
It can also be great PR opportunity for the garrison, hand out business cards, let people know what we do for charity.
If you're worried at all about it being a problem with the Legion (being out in armor, and not participating in a 'sanctioned' event), then don't affiliate yourself with the 501st during that time.
I've done the walk abouts in town, get great responses from people and it's really fun to get to bring that to people for no reason at all, but always maintain a strong moral code, don't accept money from people, stay away from inappropriate photos, keep what you say to people clean, etc.
There is also a safety issue to consider if you walk about by yourself without a spotter who can keep people in check. You can't see everything going on, make sure your armor can take some abuse in case some punk gets out of hand (loose parts are a no no, make sure nothing can get pulled off), try to stay away from large crowds because the more people there are there chance for something getting out of hand grows, you don't want to be the trooper on youtube having a fist fight with some jerk.
This is just me talking, i haven't backed any of this up with the legion charter. I've helped out car washes with kids raising money to go to a camp: It was a sunny saturday so i suited up and walked down and offered my services (for free of course) It's a real privilege to get to help out so spontaneously and bring that to peoples days, but you do need to make sure if you do anything in the armor it isn't going to look bad for Lucas.
That's how i feel about that.
