One of the main reasons why wiring buttons and logic to GND is favoured (and then copied all over the internet) is because of power optimization.

• Pulling a pin LOW with resistor to GND costs 0 watts.
• Pulling a pin HIGH with resistor to +Vcc costs power.

On complex circuits or circuits that rely on batteries this power is very precious.

Other reasons include low EMF generation. On Wireless devices pulling logic high will cause unnecessary cross talk on extremely sensitive RF receivers. On such transceivers there is a GND plane used to filter noise and this is where all logic gets pulled down to. The processor then uses the GND plane to filer switching noises.

One of the main reasons why wiring buttons and logic to GND is favoured (and then copied all over the internet) is because of power optimization.

• Pulling a pin LOW with resistor to GND costs 0 watts.
• Pulling a pin HIGH with resistor to +Vcc costs power.

On complex circuits or circuits that rely on batteries this power is very precious.

Other reasons include low EMF generation. On Wireless devices pulling logic high will cause unnecessary cross talk on extremely sensitive RF receivers. On such transceivers there is a GND plane used to filter noise and this is where all logic gets pulled down to. The processor then uses the GND plane to filter switching noises.