That list is the same as the smartlighting list – – it means “when in any of the checked modes.”
Again, as @WB70 mentioned, “night” on that list is the name of a mode. The system can only be in one Mode at a time. It doesn’t mean that the system will know that it’s night as in after sunset – – if you check that box, it’s just going to check to see if the mode value is currently “n i g h t.” So in this context, it is not possible for the system to be in “away” Mode and in “night” Mode at the same time. The system only tracks one mode value at a time.
It is possible for you to be in the “armed away” smart home monitor state and “night” Mode at the same time because smart home monitor armed state and mode are two different things. But the listing in your screenshot is just a list of mode names, and the system only allows for one mode value at a time.
A Mode gets changed whenever you have an automation set up to change it. If you want to, you could have a routine that changes the house to “night” mode at 10 in the morning every Thursday. SmartThings doesn’t care. Modes can be named whatever you want them to be named, and changed whenever you want them to change – – the name itself doesn’t have any special meaning to SmartThings.
In contrast, the smart home monitor armed states at the time of this writing are pre-defined and limited to disarm, armed stay, and armed away. And they do have special meaning as they control whether or not the scout monitoring service will be informed when something happens.
So, in your situation, you yourself might be away from the house after sunset, but as far as your SmartThings system goes, it is not possible to have the mode be both “away” and “night” at the same time. It has to be one or the other, because your system can only have one mode value at a time, and the names of the modes don’t have any special meaning as far as the system goes.