With a few exceptions, yes.
Many of the most popular programmes are bought in from America, for example; a process which is funded by the revenue gained from subscriptions. Without Sky, the BBC would still not be able to buy those programmes in without massively upping the licence fee.
Why should people boycott subscribing to Sky when they provide an amazing array of programmes, covering a multitude of genres? Personally, I'm perfectly happy to pay the £80 quid a month because I get an awful lot of enjoyment from the channels.
As others have mentioned, if you wanted a similar...