Why not even French people speak French.

You may be surprised to hear that not every French person speaks all the French he/she is supposed to. This makes learning French difficult. You need to know at least three levels of French before, with some ease, you can engage in French in a pub. Let me explain.

I have been trying my French since primary school and failed to be able to order a meal when I was 18. When I stayed for half a year in Paris, however, I discovered one should think of French on 5 different levels. Words and expressions from lower levels may penetrate higher levels but it is a slow process. Eventually, they wind up in the Larousse dictionary.

The language spoken on the streets and in the brasseries (pubs)

Low acceptance levels are the bane of societal progress

An experience shared by many is that people in general tend to accept only what they already know or have experience of. A complicating factor is that people want a commonality of knowledge or experience, for this commonality makes them feel safe. They do not want to stand out. People who do, tend to be ostracized. Listen to conversations at dinner tables and even speeches in congresses. One would expect people to dare address the new in those places but only minor deviations are deemed acceptable and these are then only addressed in a facetious way or, as in scientific circles, as a posited reason, phenomenon, or explanation, in other words, as a suggestion or proposition, not as a fact. 

The low acceptance level of people stems from