The super short version is that the BBC does not include advertisements (other than for its own content, which are only shown between shows – there are no breaks within shows themselves). Thus, to fund the BBC, the TV license exists. So far, so fair (IMHO).
The downside is that every TV in the country is assumed to be used to watch the BBC’s content and thus the owners must, by law, pay the license fee which equates to about £10 a month.
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