Are Their any Tube Preamp with Home Theater Bypass?

Yes, it is true that the tubes in a preamp will be “consumed” even when using HT bypass. Just keep in mind signal tubes in a tube preamp last longer than power tubes in a tube amp. 12AX7’s, for example, can last upwards of 10,000 hours. I’m about 75% 2-channel music, 25% multi-channel HT, so not a huge concern for me. If you’re the reverse, it might be more of a concern, but not nearly as much with a tube preamp as if you were looking at a tube amp with a bunch of KT88’s that you were going to be running 8 hours a day between music and HT. It was for that very reason that I went with a tube preamp and solid state power amp.

If the tube preamp has a true bypass, then it does not need to be powered on, and passes the HT signal through it.

As you already mentioned, 10000 hours is a quite while and should not pose a concern, even if the preamp doesn’t have a bypass… it is 1-10 cents/hour for a preamp’s tube cost.

I am looking at this issue as well and found this helpful page listing both integrateds and preamps with HT-bypass:

It is updated but not complete (for instance it is missing Modwright).  I have considered moving my Schiit Freya plus to my AVR system, which does not have HT bypass but does have a passive mode.  Some problems I see with just using unity gain are 1) the fear of switching inputs without lowering volume, and 2) I believe that you cannot utilize an unbalanced input (from an AVR for instance) going to a balanced output to your amps in passive mode.  I could be wrong on this second point.

I have a related question.  If you want to incorporate a single subwoofer into both the HT system and 2 channel system, how do you accomplish that?  Do you simply have to use two different inputs into the sub?

Cary Audio SLP-05.  End game preamp. Has HT bypass. 

The TAD 150 Signature has it, if you can find one ( used only).  It’s passive, so the pre doesn’t need to be powered up.