Why put English subtitles on an English poetry video??

I run Viral Verse (a website like Moving Poems) which features video poetry. I regularly crawl the net for new (and old) work. For some reason I cannot figure out, poetry videos often have the verse both spoken and written. It’s horribly distracting and a total waste of the poet’s (or actor’s) voice. We can’t help but read when we see words on a screen, but having 2 voices in my head – the actor’s and mine – becomes irritating .

I’m at the point now where if the subtitles start I turn off the video. English movies don’t have English subtitles. Is poetry so bloody special that it has to be drummed into the viewer?