For example, because the Internet and much of personal computing originally were developed in the U.S., the whole world accomodates English and the ASCII character set. If that doesn't seem like a big deal, then imagine if you had to adjust to German, Arabic, or Japanese.
And there is the the UK cashing in on their former dominance again: Because their empire included N. America, the world operates on their language (and a very similar culture).
Or just go to China and see so many people dressing like Westerners, using western techology, etc. Much of what we assume as 'modern' society is western; just think of automobiles and their basic design, for example, or the telephone, TV, etc. Imagine how it feels to see that all your tech was developed elsewhere (which is an unfortunate accident of history and a situation that probably won't last much longer).