[jelkand]

It’s not hidden. It’s just on the bottle because it’s convenient for a keeper to reference.

[mikemitchelldev]

The bottle was wrapped in a towel.

[Shadowed_]

I can't say for them, but towel is good heat insulator and can keep bottle content cold. I use it often for that reason (either towel or other clothes that's already in backpack).

[boomboomsubban]

I have no idea what the Euros rules are, but this could have been him wanting to keep all his stuff together without the paper blowing away.