why ubercart catalog does not have thumbnails coded in?

i created a catalog (category), and term A and term B. i have product A, product B, etc. i loaded pictures to term A and term B, as well as products A,B...

now if i click my catalog, it shows my terms A, B and their thumbnails. if i click term A (or B), it shows all the products within in the grid format (that's how i chose), but without a thumbnail. however, if i click product A (or B...) it shows the product description with a thumbnail.

i checked the source code of the page showing term A, it does not contain picture files for the products within.

my question is "does the ubercart cataglog have thumbnails?" it appears "no" because of the source code does not contain one.

but i saw most demo sites have that feature. so is it a custom feature, or is it my setup issue?

thanks.