That's how it should work, you use the service so you should pay for it. However it is incredibly unfair to ITV that you need a licence to view their channels which are funded by advertising. That condition should never have been included that any live tv needed a TV Licence because it damages commercial channels.
In that case, how did they come into existence?
A TV licence was required to use a TV before commercial channels existed in the UK. TV licences were introduced in 1946, with the first commercial stations not broadcasting until 1955.
Those first TV licences were required to use a TV set, without any reference to the BBC or other broadcasters. And it basically stayed that way until new rules were required to cover cable and satellitre TV, and later internet coverage.
I really don't accept that requiring a licence damages commercial TV in any real sense.