The only thing I could do was add an extra blank column on both sides of the table (the width of the shade extension). Then used the cell fill on all the columnns. That shaded properly. The only issue, of course, is the white space above and below the table, which can be fixed by adjusting the offset on the previous paragraph so it goes down to the table; and adjusting the paragraph below so the offset fills in above.
I tried to do a rule above/below on the table of the proper length and offsets and shading, but it didn’t work. I had thought it would as you can do it on anchored boxes. But apparently not on tables.
Hang on–I cut and pasted the table and placed into a separate text box and anchored it. I kept the fill-in in the cells and deleted the two outside columns I earlier used.
Since the table box is not technically a table now but an anchored object I was able to use the paragraph above and below for the rules (with the offset and shading. The top rule was huge (100 point).
Creating cell styles for the shading, and a style for the paragraph return that is the table anchor could speed things up.
It will require cutting and pasting the tables into boxes and anchoring, and tweaking the rules above/below on some tables, but if you set the to rule to really big, it may not be necessary. And add the text spacing above/below to the anchored paragraph style.
I’d guess a hundred or so would take a half-day to set up that way.
I guess it depends upon how much time you have for the project and the budget. And how often you get jobs like that.
It may be cheaper to buy Obi’s script.
David: I did try to use the paragraph shading to extend past the table (before it was anchored as an anchored object) and the shading stopped at the top cell. It wouldn’t go past it.