Freeview is a business just the same as Sky is. (It's jointly owned by the BBC, ITV, C4, Sky and the transmitter operator, Arqiva). Just like Sky, it charges broadcasters for access to its services. Those broadcasters have to examine the costs involved and decide whether the revenue they'll get from advertisers is great enough for a particular channel to be shown on Freeview. ITV have obviously decided that they can't afford the costs of broadcasting ITV4+1 on Freeview. However it looks like they're keeping the channel available for just a couple of hours a day as a 'placeholder' for possible future services on Channel 62.