That's why the Gogoat you ride wears the banner that appears in the video footage of the city (that Gogoat in-battle do not have). Also, in
the concept art of the male protagonist riding a Gogoat, you can see that, on the left, instead of a bus stop, it's a Gogoat Stop xD
While it would be disappointing to only be able to ride Gogoat, it kind of makes sense. There really isn't much winning in this topic, to be honest. Gogoat is
the Riding Pokémon. If there were others you could ride, it would end up like Amity Square: "Why can't I bring my Mudkip? It's cute!" Maybe you could ride Rapidash and Arcanine (because let's face it, while you can Fly with foot-tall birds, you just
can't ride 'em all), but then someone would be upset that you couldn't ride Rayquaza.