In these days of Eamon and Frankee topping the singles charts I doubt very much that an off the cuff, f-word in the middle of a song is going to seriously affect the DVD's sales. I can't imagine that Eminem's or Metallica's DVD's are expletive free and they seem to sell well enough.
In Glasgow, though, he did use the word "motherfuckers", frequently when talking about the crowd. I don't know if that was the case in Dublin as well.
As far as playing it in stores goes, in every major music chain shop I've been in lately they either have some appalling, interminable in-house, radio station playing or CD's completely unrelated to whatevers showing on the video screens - so, again, can't see it making much of a difference.
That is my avatar!