Per your post above, I don't think "non-profit" (or "not-for-profit") and charitable are one and the same thing. I'm not an expert in this area but I think there are many not-for-profits which aren't charitable (and have an explicit political purpose, for example). Someone please correct me if I'm wrong.
Your point about prevention is an interesting one, but again I think it could be easily construed so as to fit within the accepted "heads" of charity, which are:
1) Relief of poverty
2) Advancement of education
3) Advancement of religion (boooooo)
4) "Other" purposes beneficial to society
(See more here:
http://www.cra-arc.gc.ca/chrts-gvng/...bjcts-eng.html)
Included within #4 are "addressing and preventing problems faced by youth" and "addressing and preventing problems faced by families", which "prevention of addition" could easily be classified as. Prevention of homelessness could easily be classified as "alleviation of poverty".
As I said above, it's not necessarily WHAT you do, it's how you DESCRIBE what you do. The CRA is not objecting to charities which attempt to prevent poverty necessarily -- they're saying that, as your defined charitable purpose, is unacceptable because of what it could potentially admit.
Ah, the law. Strange old broad.