Being in a startup means going to startup events to meet other startups and talk about startups. You may think of a “startup” as two guys working feverishly in a garage and suddenly dropping the bomb of a revolutionary new product onto the unsuspecting world. But what I saw is best summarized by a friend's comment: “have you actually seen them ship anything?”
Business is about earning money, and you do that by delivering something of value to a customer. A “customer” is, by definition of a befriended accountant, “someone who paid.” Startups, in order to be legitimate businesses, also need someone to pay and they indeed find such people. They're called venture capitalists.
Now, before you start sending me examples of startups actually delivering something and getting paid for it, I assure you I've seen them. I just wouldn't call them startups. You won't meet their founders on most startup events. You can meet them at work, when they're not meeting their customers, or spend quality time with their cherished families. They're just plain, old businesses.