I am sure you could wrap the bars properly without any adhesive, but I find it just made the job easier. The cotton ribbon doesn't stretch much while wrapping it like the Benotto celo tape does, so it will not go on as tight. Once complete, it should also provide some grip for the tape so that it doesn't slip or begin unraveling while riding.

Also, I should have mentioned this in the original post, I found that approximately 5.5 meters was more than enough to cover my handlebars (45cm Nitto Grand Randonneur) with a bit to spare. Having the extra is always helpful, especially when you are trying to match the bar wrap to the saddle by trying different combinations of shellac and bar tape. I used the extra as test strips to achieve the proper colour.