I suppose it is may be because English is their second language, and as English is such a widely spoken language they can't always communicate in the local dialect that you are familiar with as your version of English. Let's face it a lot of US and UK English is completely different - if in the UK I said I wanted a faggot, it would mean a tasty meatball dish - in the US I know it means something entirely different!
The simple solution is of course to learn Hindi, Bengali, Telugu, Marathi, Tamil, Urdu and Gujarati.