The energy wasted isnt just the electricity to run the pump 24/ its the
heat radiated off the pipes. in the winter it helps warm your home but
in the summer its just adds to your discomfort and AC bill'

Here I have about a 40 foot n from tank to bath. I rarely wash my hands
in warm water unless someone else was already using it. but do cold
hands matter probably not. for me

dont want a cold shower though So I let it run a bit before getting
in.

over the 50 + years this home has been here thats probably a LOT of
water and gas wasted Although I havent lived here the entire time,
just 33 year or so.

I would install the circulator pump with a button AND run always and
timer
setting. then use it however works best. if your showering a quick
button press with a few minute wait while you get stuff together
probably doesnt matter...

while waiting for warm water to wash hands might myself I would make do
with chilly water at sink.

but a system with button, timer, or always on leaves the customer to
decide whats best for them and can be canged accordingly