Hi chronoboi001,
Because security wise the World Wide Web is "broken". The reasons for this are two-fold, users are not security aware. How many normal users aren't even interested in security or do not bother, because it is a nuisance, and cruise the Internet without a firewall, without any form of anti-malware, more-over only a tiny majority of users have the Operational System (Windows for instance) and third party programs updated to the latest versions and fully patched. A sort of similar situation is found with a lot of developers and webmasters, server admins etc. And the attentive malcreant and average cybercriminal uses a year old vulnerability and ruins the security of Internet further.
Now so-called reputation link checkers do not help much, only those that do real life scanning and then not only for the local domain(s) but also for the malicious re-directs. So the security the normal user relies on, does not work in these cases, well more often not than it does.
What is at the crux of the matter and where can we protect our browsers, because these attack vectors attack the user of the browser. Use in-browser security, like blocking these scripts from running with NoScript extension, you have to get accustomed to using it, but you learn that quite easily, use an extension like RequestPolicy, where you can block just these malicious requests by the browser.
And you are protected by avast shields, that alert when it finds traces of these injections or obfuscations often found on these hacked sites. Another complication is that a site could have been clean once, get infested for some time, is clean the other day. Old protection do not work here, iFrame hacks serve rogue AV to the unaware users, and this means there is enormous money involved here.
So who have to clean up their act - the user that does not want to learn and clicks, and the owner of the site that is hacked that has no proper security installed. But the final line is we have to get used to a complete newe situation, in days of old mails could mean danger, then dark alley sites, now the danger can lure from everywhere on the Web,
polonus