Can you touch the tubes?

Bulbs that run very hot like halogen bulbs need to be kept free of oils.  tubes, not so hot.  use your fingers and don't drop them.

For some amps it's difficult to use the base of a tube to push and pull into socket. I found if I just grip it comfortably around the upper portion of the tube and rock it back-and-forth while applying pressure as it slides in.  Of course there's always a fear the glass will shatter but I spread the distribution of my fingers which I think reduces the risk.

If you try to squeeze an egg in your hand with a lot of pressure it won't break but if you start angling your fingers into the egg it will break. I'm not gonna try this with a tube.

if The tube shatters who knows what happens at that point aside from losing 50 to 100 bucks on the tube and debris field. 

I have the Audio Research Ref 750s and they have about 36 KT150s. I use my bare hands. Never had a problem. Oh and about white gloves ? Never ever white gloves. Only use black gloves. 😂

Yes you can touch them 

For better grip I use nitrile gloves.