When getting a list of shares, PowerShell responds with, "Cannot validate argument on parameter 'Path'. The argument is null or empty..."; happens on any system after the last drive share is listed (C$, D$, E$, etc.), while anything else is listed just fine.
FYI, the Pad-Object function just adds lines before and after the object. Using only your suggestion without Pad-Object returns the same error.
It's very odd that all other default shares, that are drives, do not have this error; only the last one listed. C$, Admin$, IPC$, etc. all list without the error. Tested systems: Windows 10 Pro, Server 2012 R2, Server 2008.