too right...
if, however, it's just for presentation purposes :
try splitting your data ranges into two seperate sheets, making each's column widths as appropriate
then on the "tools" toolbar, use the camera to take a snapshot of each sheet and then paste both images to a single sheet
with a bit of acquired skill via practise, you can simulate a single sheet with different column widths......
one caveat though, no two caveats :
1) snapshots are limited to page size so may not be practical with large data ranges
2) you'll be farting around more often than Terrence and Phillip before it becomes second nature....
still, in the absence of anything more positive, this might be your only option