[angrow]

The purpose of copyright and patent laws is to give the greatest benefit to society (in the American constitution, the phrasing is "to promote the useful arts and sciences"). The granting of temporary monopolies to registrants is a common tactic used to achieve that end, but not the only possible one, and one that admits of many variations (terms, extensions, and limitations vary across jurisdictions and over time).

Maybe some people think that the exact laws we have right now are the best possible at serving the underlying purpose of the long-term enrichment of the public domain, but many seem to think that improvements could be made.