They kind of do. Prices for synthetics are typically ~ 75% of the natural equivalent. For CVD synthetics, there's significant margin in that pricing, margin that could be used to initiate price wars.

For now, the synthetic vendors are riding on diamond's traditional high pricing as sustained by artificial scarcity. They're cheaper than the naturals, but not all that much. I think it's their way of maintaining high margins during early business & market development.

I expect pricing to change when there are more suppliers and sales channels. Probably a couple of years to a definite downward inflection point.