Oops, I forgot to add my own answers,lol.
I have actually noticed CF leaving individual coupons on those certain products.
I also do a little CF action myself. I belong to the coupon trains, but the ones that will soon expire, I will take to the store if I am going around that time(if not I donate to Coups for Troops) and either I put a few in each area or:
at my store there is a automatic coupon machine(not the catalinas even though we have them too) but you scan your customer appreciation card and it shoots out a few coupons , I will leave them in the tray of extras.
My thing is: every little bit counts, can't stand to see it just thrown out.