Okay, this isn’t exactly about two “cities”, Fort Saskatchewan (hens forth, “The Fort” as the locals like to abbreviate) is not exactly a city, but close enough when talking about “small cities” (15K as of 2006) compared to Sarnia, of around 75K.
We are talking about two places: one that acts as the regional focal point in south west Ontario, the other a suburban annex of Edmonton Alberta. The differences, me thinks, are more due to the suburbia effect.
To illustrate with pictures, here are what I feel are the four best pictures I took in each city:
the four best of Sarnia
the four best I took at The Fort
For Sarnia, I had a hard time picking four pictures. For The Fort, I had a hard time taking four pictures. The old part of the town seems to be dieing out , with what little charm there is mostly being around the river, and downtown, such as it is. The new developments are exactly what you would see in any new Calgary suburb: a wasteland of parking space with trademark stores and big box retailers to drive between. It is sad that in ten minutes of walking I passed four liquor stores, three fast food places and not a single restaurant. Then again, I had no business walking in that parking lot in the first place. The only thing I found of interest was this: 
Calgary needs some of these rather than the flashing hand so you have an idea how many seconds before death cometh forth in the form of rumbling steel chariots to smote you down. But it certainly ain’t a pretty picture - just shows the same suburban character that you would see anywhere on the outskirts of any city here.
Sarnia had more places to eat than I could try within walking distance of my motel. The Fort had a bunch of franchise places, with a few restaurants in the downtown core. The one place I tried that looked at least somewhat promising was okay, but nothing I would want to eat at more than once in a while. In Sarnia, I found a nice classy place to eat (attached to a Super 8 motel - go figure) and a great pub with good food, good beer, good price. Try finding that in Calgary these days.
Sarnia had some nice old buildings in it’s downtown core. I’m not sure what The Fort ever had. The mall (currently deserted, to be renovated) gobbled up a fair bit of the old town area, along with some new buildings of bland design. Speaking of deserted, I decided to try the Smitty’s for dinner (being the best and only restaurant choice within 20 minutes walk) and found it to be closed due to lack of staff. When I end up hitting the McD’s for lack of better choice, I know things are grim.
Now, I’m not ragging on Ft. Sask. here in particular, Airdrie, or any suburb community in Calgary is no better - they all have these mega-shopping areas that are suited only to driving your car to, from, and between stores, with no charm, or unique character that would tell you where you are. I have no idea why people shop at these things. At least in a mall, you’re inside from the elements - here you need to shop, walk to your car, drive through snarled traffic to the next store 2 minutes away, and walk to your next store, repeat. Hell, I’m sure Sarnia has one of these shopping places tucked away somewhere I didn’t get to, thankfully.
I can forgive the lack of character and walkability for the Fort, I can forgive the liquor store on every corner (this is Alberta), but I cannot forgive the total lack of anything approaching an interesting restaurant. It just seems insane that the only way to go and have an interesting dining experience is to go into Edmonton. But perhaps that is exactly what the Fort is tailored to - literally a bedroom community where any quality time is spent back in the big city. Doesn’t do much to foster a sense of small town living, which is what these ‘burbs are supposed to be about.
