A Dissent:

In all fairness, we have to keep in mind where Anime comes from and how that differs from where our particular predispositions come from.
If you're from the North America, odds are pretty good that your ideas about animation have been influenced by a limited number of sources, most likely including Disney, Warner Bros., Hanna-Barbera, and the M-G-M studios. (There are others, to be sure, but these are the big producers.)

Animation is painfully expensive to produce. Each second of film has 24 frames. To make something move smoothly, you need a new drawing to appear about every other frame. That means most American animation needs 720 drawings for each minute of motion for each moving item. And you still have to pay someone to draw everything that is moving on screen.

Most well known American animation was produced for theatrical release. All the classic Looney Tunes, Tom and Jerry, most of the "Disney Classics," were all made to be shown in theaters, 'cause that was how cartoons made their money back. Most television animation doesn't have a comparable budget.

Which is why cartoons like Scooby-Doo, The Flintstones, The Jetsons, or anything from Filmation (like He-Man, She-Ra, or Fat Albert) used what are called cycles. They couldn't afford to re-create footage of characters doing things like walking for every episode, so they re-used the same footage over and over and over. If you look carefully, you can see the same walk cycles showing up again and again.

In Anime, rather than re-use the same footage, many directors chose to simplify the animation by using fewer different drawings per second. In America they used more drawings for shorter segments and re-used those segments. In Japan they didn't re-use the segments, but they used fewer drawings. Both decisions were made with an eye to economy, and not sloth.

Of course, shows like The Simpsons and The New Batman/Superman Adventures had enough money to spend per episode to rarely have to recycle footage for reasons of cost.