Agreed with paul.
Look at musky fishing, its way more expensive and difficult, and even in the best waters it will still give you the skunk frequently. Also too there is very limited waters you can even target em, and you need a boat and expensive gear to have a good chance at a bigun.
As for walleye fishing, they are in fewer locations as well, and you typically need a boat to have a decent chance at em. They dont fight as well either and are less willing to bite in most situations.
You can catch bass in almost any lake or pond and on almost anything, you dont need much tackle to do so successfullly, and you can fish em from shore. All of these factors make bass the most accessible gamefish in America. Did I mention they are awesome fighters for their and explode on baits frequently making them fun to catch!
Now that I think of it, I cant even think of a single body of water that does not have bass in it.
