it doens't bother me, if they use Kawaii sometimes.
I usually mix Japanese, English and Swedish daily '^^
so when I talk, I talk funny....
anyway,
what do annoys me if people
types/says; DesuDESUDESUDESU DESU all the time. (and only desu)
sure its cute but it does not mean anything.
its just the end of the sentence and says that something is something.
I have studied japanese for 1 year, so yeah sometimes it bothers me when people says some random words on japanese and tells it means something it does not mean.
but using the word "kawaii" once is not a way to rape the Japanese language.