The majority of America listens to country music and drives a pick up truck. So, the blue collar heroes tend to be bigger at the box office. This is only my theory... 
Well I'm proud to be an American who drives an American-made pick up truck, listens to country music and wears cowboy boots(I've got my cognac, ostrich-skin Luccheses on while I write this). But at the same time I also love James Bond. Not only that, I like it when Bond is sophisticated, wears a tuxedo, goes to exotic international locations, orders champagne(preferably Dom Perignon) and vodka martinis and meets sophisticated, beautiful and well dressed Bond girls who speak with exotic accents. I did
not care for the Bimini Bar scene in
Licence to Kill for its lack of sophistication and wish that LTK had been set in China as it was originally intended to and not in the relatively drab location of its first half. I also want James Bond to always be portrayed by a British actor, never an American one. So, just because we American viewers may be one way doesn't mean we can't appreciate someone who is different from us. I think American Actor James Garner(who would have made a great Felix Leiter back in the day) put it best on the Happy 21st Anniversary Bond special-"The thing I like best about James Bond? He's British. I think that's it." My sentiments exactly.
As to the main question, I think Bond may be more popular in Europe and overseas because American audiences have probably tended to be overwhelmed with more action heroes than any other individual nation, so that may be why Bond, as popular as he is here, is even more popular in other countries.
Proud to be an American James Bond fan since age 10.