Libertarians obviously understand the concept and requirement for consent. Until they don’t? There are entire books of excuses written in attempts to justify copying intellectual property without consent. Granted that intellectual property laws need to be reformed, morally you still need consent to copy someone’s original work.
“What the patent and copyright laws acknowledge is the paramount role of mental effort in the production of material values; these laws protect the mind’s contribution in its purest form: the origination of an idea. ” -Ayn Rand
I hope you understand that the following meme is all in good fun.