The reason some are against them is that they present audio that has been altered from what was present in the original file. By "coloring" the sound, you are making changes not intended by the people who did the original mastering job for that song, altering what they already determined was the correct presentation.
That said, EQ can compensate for things like room acoustics, headphone response curves, etc. It also of course can make things sound subjectively "better" to the individual listener, depending on what he/she finds more enjoyable (original intentions be damned!). In that sense "I am a savage violator" (Nico - Innocent and Vain), I do use MusicBee's superb built-in EQ and a VST limiter/compressor to get the subjective sound I prefer (and to fix clipping distortion in some radio streams).