Maybe its a board for those that want extreme disk redundancy for a long term running service? Build out two or three in failover or have load balancing and go from there? Honestly i don't see the market either, although i would love to see 32 sata SSD's in RAID 0 for funsies. Oh hah, thats another option i guess, extreme io using nothing but a motherboard with sata 3? Eh, you're better off with a decent raid controller hah.
Side note:
Its just kind of a weird board, and maybe theres another version with more scalability? There are clearly unpopulated spots for more fan headers, as well as support for up to 4 sodimm slots instead of the two it currently has. Theres also the onboard displayout instead of just using the vga port. Finally, a general annoyance, the x1 pci-e slot has a closed back, which is annoying because if it had an open back it would allow the use of pcie cards that are more than x1, obviously just not at full speed. This severely limits the cards you can use, more so than the general layout of having the sata port so close behind it would.