I beg to disagree...I do not know kannada and i got my work done from many govt department without any issue of language barrier....Native kannada speakers are very nice, humble and understanding people. As i understand, hindi is 2nd language in Karnataka schools and local people understand hindi. Their only expectation from non-kannada people is to respect their local language and culture.
However, handful fringe elements are present in each community/religion/state and they spoil the name of entire community/religion/state.