Because of the fur trade.
The fur trade was main form of economy for the French colonies and the French got their fur from you guessed it, Native Americans. French colonists are an exception when it comes to dealing with Native Americans as they had good relationship with them and did not thought of them as inferior. They traded European goods for furs and the Native Americans even helped them by showing them goods hunting spots. So their relationship was one of cooperation.
Spices (a luxury good) among other things, but spices is the most important
There take of the constitution under my understanding is that if the government does something that makes the people unhappy they can look back at the constitution and say you are braking this law and now you are being over turned.