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I have noticed that quite a few shuls have candles or electric lights at the amud where the chazzan davens from. These are well lit establishments and I don't the lights are there for a practical reason, especially when they use candles. It seems that this is a more chassidish minhag.
I can't think of any reason other than that it used to be a practical necessity, no longer is, but as we often find, people just haven't changed their practice.