This is a problem in small cities across the country, and of course it has been going on for quite some time in Eugene and elsewhere. But "blame the liberals" is unfounded: see for example last year's US Supreme Court decision on Reed vs Town of Gilbert, in which the majority opinion was written by the conservative wing of the court (Scalia, Thomas, Roberts, Alito), which had the effect of strengthening the "right to beg" via signage and verbally. See American Bar Association summary "Panhandling And Solicitation: Understanding The First Amendment Implications".