Thats almost like saying, PVR's should be banned as users have the ability to forward through them and skip advertisements. Or other channels must be banned, so if you are watching serial XYZ on channel ABC, you must continue to watch it including the ads and not skip it.
However, you look at it, if you try to block users, people will just drive traffic away from that site as it is no longer considered as "compliant". Compliancy states that there must be a norm which all users have equal and open access. Give it time, I'm sure someone in the US will sue the website owner on the grounds of non compliance, or inaccessible information, or something similar where you are being biased.
If you want to see something stupid, visit hdfcbank.com and check out netsafe and then login. It says IE as minimum requirements. Honestly I dont see the reason for this, but yet its there. According to this, if you use Internet Explorer, you should use a netsafe card, but at the same time you need IE ? See a pattern of stupidity? Its like if you want to use the site, dont use a browser thats safe, however, you should use a netsafe card if you want to be safe.
Anyways, if there are any other sites that stop you, you could just simply change the user agent in about:config. What are they going to do next? Block Internet Explorer?.. hehe
Regards, Satish