Like others have said, it's because they don't really understand the game and the strategies behind the game. They are also used to fast paced sports like basketball and football so to them, baseball is boring because everything is SO slow. I also agree with the instant gratification thing someone else also brought up as touchdowns and scoring baskets (or blocked shots!) are exciting while home runs don't happen every inning unless you are in Coors Field (jk!).

On a slight tangent here, I came across this little article written by well-known entrepreneur Seth Godin. It said..

Hitters don't have much of an agenda other than, "swing at the good balls." No one blames the hitters when the pitcher has a hot hand and throws a no hitter.

Pitchers, on the other hand, decide what's going to happen next. Pitchers get to set the pace, outline the strategy, initiate instead of react.

When your job is in reaction mode, you're allowing the outside world to decide what happens next. You are freed from the hard work of setting an agenda, but in exchange, you dance when the market says dance. "I did the best I could with what was thrown at me..."

Finding the guts to move up the ladder is hard. When you decide to set the agenda and when you take control over your time and your effort, the responsibility for what happens next belongs to you.

While I get what he's trying to say, I felt that he demonstrated a lack of understanding of the game of baseball. Yes, the pitcher sets the pace of the game, has a strategy on how to pitch to a batter and the batter needs to react to a pitch thrown by the pitcher. However, if a batter (let's say Mike Trout for example cuz he's Mike Trout) is 3 for 3 today with all XBHs, Trout is in his head now. Of course, SP still wants to strike him out but he also knows he isn't fooling Trout today. I can imagine pitcher either intentionally walks him or pitch around him hoping he would swing at bad pitches. In this case, I say batter is in control and pitcher is the one adjusting.