http://www.macleans.ca/tag/fort-mcmurray-faq/
The boreal forest in Canada is a very big swath of vegetation. It burns every year, sometimes more destructively than others. The Mountain Pine Beetle is killing the pine forests, which greatly adds to the fuel mass available. The logging companies can only cut so many marketable logs per season.
There are whole communities and subcultures that depend on fighting wildfires. There are also individuals whose summer income depends on getting hired on to fire crews. It is not unknown for the same people to start a bush fire and be hired to fight it or others. All this is to say that yes, Ft Mc's "The Beast Fire" as it has been named, has been assessed as human originated. However there is no announced plan to hunt down and prosecute the one poor bugger whose ATV exhaust sparked a fire. It isn't the first and it won't be the last human caused fire. Nor, is there any way to investigate in sufficient detail the cause of the fire so it would stand up in court. Unless someone walks into the police station and convincingly admits to starting this particular fire, we may never know exactly how it started.
As to a perceived lack of urgency, Canadians are almost painfully civil to each other. We apologize for wrongs (and rights). We tend to respond to official direction without being confrontational. So, when the fire chief, who in emergencies has more authority than a mayor or the police chief, orders people to leave it happens. The kindness of strangers is not an abstract concept but how people treat each other unprompted. (Ever ask why this forum is so generous and helpful ....?)
There may be discussions on why some parts of town were evacuated later than others, or when the orders were issued. Or, whether the fire was fought intensively enough such as whether a particular type of air tanker should or should not have been contracted. Such conversations based on speculation won't advance the issue, nor should the uninformed be allowed to steer the debate. Most politicians have learned to stay out from underfoot, and let the professionals deal with the problem. Their managers and political ministers are responsible for answering those questions.