Probably because BTE is an unapologetic 1:1 clone of bitcoin, while this bytecoin is brand new and innovative with a completely different algorithm.
Plus bytecoin sounds great as a successor to bitcoin.
I causes confusion for both coins. If they can't do the basic check to see if the name is in use, that may make some people cautious of how much care they use in other areas.
Or probably because they called the coin Bytecoin before BTE appeared.