Why do some people think french people are cold?

A recent international survey showed that the french capital was one of the most hostile touristic destination in the world.

French people are not open to speaking to strangers, they also don't speak very good English that's why tourists get the wrong idea that they're being rude.

At early times, the word humor was not allowed in the french language. Not until 1932 did the french academy allow the word l'humor in their language.

French people are arrogant and they're used to criticizing a lot.Which give the wrong idea that they're rude, however some other people think that it's just something that they're used to.

French people don't smile a lot and they tend to be more hostile than friendly. They don't usually smile or to talk to strangers in the street. (See Why some people never smile?)

The french government put a rule that 50% of the music played on radios should be in french, almost every document, every business communication, everything is in french, this rule limited their access to English knowledge.

French people are not used to showing off their feelings exaggeratedly to strangers. This usually seems rude or cold behavior to some people, when it's actually shyness. 

Some Americans tend to believe that french people are cold because they don't make random comments like they do, however other people think that french people are just used to keeping their mouth sealed if they don't have something important to say.

In France, formality and etiquette are rules to people. They dont usually aquentance with someone unless they were introduced to them. For instance, if someone goes up to a french guy and say' hi, I'm Jaques' the french guy would find it unacceptable. (See How to be assertive without being rude?)

French people are usually honest, they like to say what ever they want and always complain about whatever bugs them.

Shop sellers usually tend to be rude if you don't say "bonjour" before you ask for what you want.

Many french people have a lot of misconceptions about foreigners. For instance if you're a Romanian they'll immediately think that you're a thief.