Cause when you can afford the big ones and set up an Atmos system you will stick with the brand and will buy the small ones anyway. And when they are too cheap they can't be good. Maybe manufacturing in a higher wages country. Less pieces sold over all, too much overhead.If it costs double , there must be a reason
Or they just want to earn more money with less pieces sold and know their customers are ready to pay a little more to be in the cool PMC gang.
Look in the HiFi market. Technical quality is not what the price makes ...