Cases that have addressed links and copyright dealt with the permissibility of "deep linking"—linking to a page other than the home page—which, of course, is indeed permitted. Ticketmaster famously lost a lawsuit against Tickets.com about just this. But that case was about copyright infringement; by making a trademark claim instead, Jones Day opened up another legal avenue.
The Internet is a new marketing frontier where the rules and regulations are rapidly evolving. Governments throughout the world aim to redress this imbalance by providing protection to their citizens through laws and regulations which control the use of advertising.