Check these links for an introduction:
[url=http://www.media-awareness.ca/english/resources/legislation/canadian_law... regulations[/url]
[url=http://csc.lexum.umontreal.ca/en/1989/1989scr1-927/1989scr1-927.html]The Supreme Court decision - very interesting[/url]
[url=http://rabble.ca/babble/youth-issues/ontario-ndp-wants-ban-food-ads-kids... real-life examples of enforcement[/url]
[url=http://www.opc.gouv.qc.ca/WebForms/CommuniquePresse/CommuniquePresse.asp...'s a release (in French)[/url] from last July about McDonald's pleading guilty to 6 counts of violating the Act. Burger King was similarly condemned in an earlier case.
The fines are puny - but the violations themselves are the exception rather than the rule. Generally speaking, the rules are respected, and it makes a huge difference in terms of the climate IMHO.
Your questions are all good - but when you start with a social and political will, and legislation to back it, you can answer those questions.
Wow...thanks for those links!! I'm going to take a look at them.