I like you guys who think up new ideas for functional devices, especially if the mod is dirt cheap.
And I love that idea of bowling bags... just make a wire hoop under support that goes under the bag, up the side of the ped, over the top, and down the other side.
A great source of stiff wire are those election signs local politicians put all over the place.. wait till the day after the election, and go out and round up 20 of them.
You'll have to do a bit of welding maybe.
Then you can rattlecan paint the bags.