I just realized that there is a new entry in the electrical type drop down menu. Do you know what the purpose of Free is? It’s not yet present in the official Eeschema documentation so it must be pretty new.
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“Free” by default can safely connect to any pin, in a similar way to passive. However “passive” does generate a warning when connected to an “unspecified” pin, while “free” never generates a warning.
Essentially, you’re “free” to connect the pin to anything you like.
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Sounds like a “Get out of ERC Jail Free” card.
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The other way to think about it is that “Free” pins can be routed through if it’s convenient on the PCB. There may also be “no connect” pins where it’s a bad idea to connect anything at all to the pad. But, for cases where the pad may be connected to anything without any bad effects, it can be useful to connect it to whatever net needs to be routed through the area so that you can route across the pad.
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Thanks for your feedback, that functionality is actually what I was looking for recently. Though I did not know it already existed. 
My use example:
On some Microchip EEPROMS, pin 7 is write protect high, but on some models, the pin is “not internally connected”. I wanted to lay out a development shield board with an 8-pin DIP so I could use different EEPROMs. I chose to have protection always disabled, so I connected pin 7 to ground (protection off, or don’t-care). The librarian who made the symbol for a particular part made the pin “bidirectional”, which gives the ERC warning, “Pins of type Bidirectional and Power output are connected”. I just want it to connect to GND always. “Free” fixes the warning. (Some production layouts also tie WP to ground too so to not waste a GPIO output, so it’s useful for non-development board too–we won’t talk about noise causing spurious writes :-)). So nice!
Actually, “disconnected” works as well (no warning if connected to Vcc or GND).
Perhaps I need to think this through some more, no?
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