Nintendo Switch: Differences between Digital purchase and physical copy?

[Silicon Switch]

I bought a physical copy of Breath of the Wild for my switch. I noticed that it asks which user is playing when I launch it, and allocates a save file for that user. I like this feature compared to the traditional three save files, because it means I can share my game with my family of more than 2 other people, and if I want to see what it is like to start over, I don't have to erase anything.
I downloaded the Snipperclips demo, and noticed that it does not ask about who is saving.
I was wondering if this is because Snipperclips is a demo, or if it is because Snipperclips is a digital download. Does a digital download of Breath of the Wild for Switch create a save file specifically for whoever is playing, just like my physical copy, or does it only support one save file, under the assumption that the person who signed in to purchase the game is playing?
I would make a digital purchase to find out, but $370 is already a lot to spend on video games in a month.
The answer to this question will determine if I will buy physical or digital copies of other games.

I see 2 people responded that they bought a physical copy for WiiU and 1 responded digital copy for WiiU. Does the game do the same thing on WiiU as I said it does on the Switch? I guess my first question is, "Does the WiiU have the users system like the Switch?"
I don't know because I skipped the WiiU.