Truly, those are two enigmas....
The Colt .45s graphics should definitely be on the front side, since they came first. Cannot conjure up a reason why the Astros portion is on the front.
The Expos Pennant may have been taken from old/existing stock. The gap between the Batter and the team name is very wide (and not the norm). So perhaps it was an unused generic "Batter" pennant that later was purposed for the Expos.
I know this process was done (to some extent) back in the day, and is the only explanation I can think of. In addition, that same generic Batter Mascot was used for many teams, as discussed earlier in this thread. So it might make sense that a small left-over stash of these was retained for this very purpose (rather than wasted/discarded).
That said, it's the only one I've ever seen, and is by far the most attractive and interesting Expos Pennant extant.
