Unforrtunately the FN-SCAR costs $2,799 new to civilians the last time I saw one for sale. The military M-16 is less than half that cost to civilians in the AR-15 version.
Quality costs, regardless of design. Yes, the cost of the AR series design is fully amortized and it's more or less in the public domain. Still high quality AR's are pricy guns.
The Navy Seals use the Knight's Armament SR-25, the final perfection of the AR-10 design that Eugene Stoner himself worked on until shortly before his death.
Over here at Impact Guns they have SR-25s between $6,200 and $9,000. These aren't fancied up builder specials, these are box stock Knight "AR-10s" that are full milspec quality for the Navy.
The DPMS AR-10 cost $1,000. The Armalites run to about $2,000. Surplus FN-FALs cost $1000 in 1985, 25 years ago. FN no longer makes them, so used examples fetch $3,000 to $5,000 depending on variant and condition. According to this inflation calculator $1000 1985 dollars is $1975 2008 dollars.
Given all these factors I don't think the SCAR is overpriced, though it may be out of reach for many people. At least some of our elite units are equipping with them.
The box fed .308 semi-automatic magazine is the choice of the thinking civilian for self defense. So far the FN-FAL is the still the best of the bunch*. The SCAR looks to be the rifle most likely to take the title from the FAL, from everything I've seen.
I'm looking forward to getting my hands on one to put it through its paces sometime in the future.
*Apologies to the M-14/M-1A fans.