As I asked in your denial of service thread (an equally bad idea).
What about DDoS (Denial of Service) to sites that don't accept bitcoin?
What is it about freedom that scares you?
Bitcoin is free (as in free speech not free beer). That includes the freedom to NOT participate. What is disturbing is not that you think it is plausible (it isn't) but that you think that if it was plausible it would be a good idea.
What right do you have to dictate who gets to see what site? What right do you have to force how private property owners conduct their business. You already have the ability to not do business with companies that don't accept Bitcoins; just don't do business with them.
Choosing not to do business with X because they don't accept Bitcoins is freedom. Trying to prevent others from doing business with X because they don't accept Bitcoins is tyranny.