Good question.
I have made some from wood as well. And yes it is way cheaper. But, this material is lightweight, won't fade, chip, crack, peel, never needs paint or stain, won't break, resists chemicals, easy to clean, can get wet, has no odor and will not hold odors, cuts easy, can be nailed, screwed, stapled, drilled, and has a nice texture. Those are just some of the benefits.
It's used in the marine industry mostly but it's also used for things like cutting boards and stuff.
I can do wood ones that are unstained or painted for cheaper but I would run into a little more labor because I would have to glue/staple/putty/sand to make them nice. So I would want $99 for them.