Ground

Yes

This has everything to do with these laws applied within this simulation though, and nothing to do with real life circuitry. Right?..

Yes and no. This kind of ground node is more like a writing/sim convenience than a real circuit issue, but it pays to understand the implications of earthed/floating devices and not just view your circuit like its own little isolated box all the time. One of my favourite examples is how most scope grounds are mains earth referenced, which can end in melted probes if you hook 2 neutral leads to different voltages, or hook a neutral lead to a wrong point in a circuit using an earth referenced power supply. Suddenly you've created a short between 3 seemingly independent devices.

hehe 3 days ago i fight with central heating pipe whose trespass my room to get through of this goo'o'paint that covered it to get to bare metal and finaly have "workground" for my freshly made dyi tube scope I desperately need fresh groun4for second probe connection. personally i never put earth wire into scope but always use a well cleaned and earth=hooked not far than few meters away neutral wire and take out scope only single probe connection hooking second probe to physical earth from total separated ground point node (at least 30m distance betwen contact point with earth of both nodes ) this distance make u leave sphere of influence betwen two earth points. this is the only way if u want to see on scope most reliable image of all common mode things that apears. there's no other way to see them bright and clear.

Hmm, that dyi tube'o'scope sounds like it wants to be posted over at ECG+... (hint,hint).... just sayin'..