I think the record company (rather than ITV) may well buy an advert slot, but I think these programmes are a winner for the TV company (so easy to make) and for the featured artists. TV exposure is worth many many radio plays- some songs featured in X factor and Strictly are often pushed back into the charts.
So I did miss the poll! Apparently voting has been going on for the last few months on the ITV website.
I don't recall this being publicised, anyone else?