People are warmer in the South of France (maybe because they're not as sun deprived as Parisians). In Paris, most are so self conscious about how terrible their English is that they project their anger on tourists! What's funny to see is how happy they seem when I help them find their way through the city, it's endearing since they think I'm gonna act like a snotty bastard... Same when I travel and people realize I'm from Paris and I'm actually nice and friendly, they don't expect that all!
Before asking for help, try to spot people who have an an open face and pleasant body language, use your instinct and don't go for the stressed ones with a permanent chip on their shoulder, in most cases they won't help you.
