Piracy/File sharing - Why aren't songs, movies or ebooks given for free (+ads) like TV?
It's called a Principal-Agent Conflict.
The RIAA/MPAA act as agents on behalf of the people who actually produce content (and consequently end-consumer value).
To maintain relevance to their principals', the RIAA/MPAA must signal value to them (i.e. claim loudly and repeatedly that they do something good for them [regardless of the validity of that claim]).
Firstly, this signaling is demonstrably an example of the Principal-Agent problem, in that it diverts resources away from actually advancing the principals' interests, but more so in that it creates a perverse incentive for lobbying groups to fight imaginary fires.
The impact of piracy on the broad economy is believed to be near zero, so IP laws are effectively just rent-seeking $^{[2]}$ anyway.
Whether or not that particular type of rent-seeking is always a drain on the broad economy (in that it distorts markets producing deadweight loss in excess of the externalities corrected) is up for discussion, though it is known to be possible (insofar as the existence of an optimal tax [or government induced market distortion] is necessarilyy proof of the existence of an excessive tax).