I'm not going to lie, what you just wrote confused me. Something about how the sentences are worded makes it really difficult for me to understand what you are trying to say.
Per the motherboard manual HERE, page 2-39. The 2xSATA3.0 and 4xSATA2.0 ports are supported by the Intel C222 PCH chip. In addition 8xSAS connectors are supported by the LSI 2308 controller.
The SATA ports aren't "useless". They just can't be used with a SAS expander. Drives could still be connected to them directly with a SATA cable instead of connecting to the backplane. The drives could be placed somewhere within the case. A good use would be SSD's for ZIL/L2ARC. This is what TuxDude had mentioned and inline with my thinking as well.
Per the motherboard manual HERE, page 2-39. The 2xSATA3.0 and 4xSATA2.0 ports are supported by the Intel C222 PCH chip. In addition 8xSAS connectors are supported by the LSI 2308 controller.
The SATA ports aren't "useless". They just can't be used with a SAS expander. Drives could still be connected to them directly with a SATA cable instead of connecting to the backplane. The drives could be placed somewhere within the case. A good use would be SSD's for ZIL/L2ARC. This is what TuxDude had mentioned and inline with my thinking as well.