Local laundromat
Like most others (the good ones anyway) along with commercial/industrial (ditto) have circulation systems on hot water supply. Thus opening the taps gives instant hot water with out having to bleed off cold as it were.
Being as this may since many laundromats have pre-wash set for "cold" and don't spin out water between that cycle and main wash; unless hot water going into machine is over say 160F, don't see how temps will be 140F or even 120F.
This could vary by climate and location, but tap water in NYC area during colder times of year is chilly. Haven't looked in ages to see if local laundromat washers mix cold and hot water for pre-wash. Know they use tap hot for part of final rinse (to flush fabric softener), but also use cold. Am guessing former is to make sure even thick gooey FS is moved from dispenser. Hint; it doesn't always work.
Now an industrial laundry can program machines to do multiple "hot" washes of short duration. After first 12 minute wash at "hot", second and perhaps third won't see dramatic drops in temps because machine, tub and laundry is already warmed if not hot.
Think main reason why laundromat washers don't bother with anything else that tap hot is they believe customers will use chlorine bleach for white loads. That substance covers up a multitude of wash day sins.