Does anyone leave their amp and preamp on all the time?

I do not leave my equipment on, as my amp and preamp shut themselves down after so many minutes of idle time and with a power unit, DAC and transport, consumes quite a bit of electricity.

It does take 10-15 minutes of play time for my equipment to sound its best.

Preamp no but my amp is always in standby.

Like others I leave mine on unless I'm leaving for at least a few days.  Warm-up time was definitely part of my reason, but I had another reason that may or may not be valid so maybe an engineering type or someone more knowledgeable can chime in here?  I noticed that light bulbs and a TV of mine died immediately by turning them on.  My uneducated guess was that the initial surge of current puts more strain on a component (maybe the power supply in particular?) along with the continual heating and cooling of all the electronics.  So I thought leaving my system on all the time may actually increase its life by cumulatively reducing stress on it rather than turning it on and off almost every day.  Was I completely off base?  Will prematurely wearing out certain parts (capacitors, etc.) outweigh any benefits from leaving a system on?  Always wondered about this, and thanks for any thoughts.  

I left the Aesthetix Io on all the time - since the sound is best, fully warmed up - but it was probably not a good idea. The time plus heat factor led to repairs. Now, I turn all my tube components off and on, even if I have to wait an hour for good sound.