Top: Furniture Stockpile; Bottom: General Stockpile; My dwarves don't seem to be storing any of my mugs in my bins, the max bins i have designated is 35? I'm in version DF2014 v0.44.09
Looks like you are out of free (empty) bins. Check your furniture stockpile or 'Stocks' from z-menu. Each bin can store up to 5 bars or blocks, while 30 or more small crafts may fit into a single bin.
Or maybe your population are too busy. Like transporting large number of items from former stockpiles to another place.