Not a criticism, just an experience. When using a cutting board, one's hands and the boards can become slippery due to water, oil, grease, plant juice, . . . , making it difficult to pick up the board to move it out of the way, to the sink, . . . As the board gets larger, it gets heavier. If a customer perceives this, he or she may decide not to purchase. A shallow centered groove at each end makes the board easier to pick up in all conditions, and is not visually distracting. Certainly more work to fabricate and sand, and perhaps an additional router bit purchase, but may result in more sales.