Wired doorbells have a transformer which is always on and always using
electricity. This is yet one more thing in the house which does this like
TV, microwave, remote control things, things with clocks, plug-in phones,
etc.

These things add up...

I replaced/rewired my switch so the transformer is only on when the doorbell
button is pressed! Thus the transformer is off most of the time now.

I installed a regular electrical box at my front door, ran 14 ga. romex from
this box to the doorbell transformer, then got a nice brass blank wall
plate, drilled a hole in this plate, then installed a 120V momentary push
switch in the plate. Then wired this to switch on the transformer when the
button is pressed. Then connected the two wires which were going to the old
button so the doorbell would ring as soon as it receives power from the
transformer.