Wake up. This isn't 1994. The World Cup is HUGE in the United States. Soccer is huge in the United States.
8 Million homes watched USA-Ghana.
8. Million. That's not a minor spike.
Also, the 2014 MLS average attendance was over 18,000. In case you were wondering, both the NBA and the NHL are below 17,500.
Wake up. Look on the internets before you pretend soccer isn't a big deal here.
That's ignoring the fact that NBA/NHL have televised broadcasts of their games. Rights to broadcasts these games are in the billions of dollars. You may have 18,000 people watching a MLS game. But that's it. No one is watching a televised broadcast of it. No one is watching highlights of a MLS game on ESPN. Hell, I live in city with a MLS team and I don't even see highlights of those games on local sports highlights. Sorry, soccer is nothing between world cups.