I don't know if it applied to ALL extended licenses terms, but it sure does apply to many, although I think this should be "print on demand" case, which is not allowed at least in IS (I didn't find a reference in DT and FT, so it looks like this is allowed).
from IS: "Items for resale limited run license required."
"Prohibited uses for both Standard and Extended license: Online "print-on-demand" products"
from DT: "Print Usage (P-EL): Physical Items for Resale: includes the right to use the photos for t-shirts, postcards, greeting cards, mugs, mousepads, posters, calendars, framed artwork that is to be sold to other customers for a maximum amount of 10,000 copies (applies as a total of each type of usage)."
from FT: "Extended license
Use: illustration of derivative products intended for resale (postcards, posters, t-shirts, templates...) "