Big cameras have big sensors that capture a lot of light and produce very quality photos in day and also at night. It is odd that people carry their camera during the day, but they put it away as soon as the sun goes down.
Maybe they don’t know how to configure their camera and they get disappointed after a couple of blurry night shots. The trick is to set the camera in “S” (shutter speed priority) mode and set the shutter speed at 1/60 or even 1/30 if your hands are steady. Then the camera will do the rest. It will open the lense to get more light and increase the ISO. With the help of the big sensor, the shots will be sharp and the light can be increased even more in post processing, if you shoot in RAW files instead of JPEGs.
Another idea is to take advantage of the light that comes from street bulbs and shop windows. It will give you more interesting results and better shadows, than the “flat” light that comes from the camera’s flash light.
Christos Sousougenis 