Can you touch the tubes?

The idea I think is you use cotton gloves to keep oil off the tubes. I stopped doing this years ago because I preferred the grip you got by using bare hands. You can wipe the 'oils' off with a cotton cloth if it bothers you. Personally I don't think it makes any meaningful difference. 

I suspect the white glove thing ties back to someone with a bad case of OCD and a good imagination.

I've worked with tube gear for over 50 years now -- building, repairing and using -- and never had a problem handling tubes with my hands. No tube failure ever from that, and no appearance issues. Tubes are made of glass, and yes, glass can get dirty, but one can also clean glass.  The only time I've ever used a cloth is if the tube needs to be handled while still hot. You don't want to burn your fingers.

If you don't want to touch the tubes something that works well is a small piece of plastic wrap like Glad cling wrap.You can still get a firm grip on them. I used to do that when I first got into tube gear.If my hands are clean I don't worry about it anymore.

Not a problem for HiFi vacuum tubes, though it's best to only touch/move tubes that have cooled down (not always doable with a musical instrument/PA amp in use/demand).

https://i.discogs.com/TU_M5i6i4CvCz7BKbVTOHYKhqR9UhAHf8DWxwpXnbvA/rs:fit/g:sm/q:40/h:300/w:300/czM6Ly9kaXNjb2dz/LWRhdGFiYXNlLWlt/YWdlcy9SLTUyMzcz/ODctMTM4ODQwNjAy/NC05NzIzLmpwZWc.jpeg

DeKay