Hard sided water bottles slosh when partially full and make noise. For hunting I like a platy along with a hard side. I drink from the platy and then refill it from the hard side.

Clear bottles can be used at lower latitudes to purify water by the SODIS method.

Dark bottles with wide mouths, like the brown prune juice bottles, can be filled with snow and set in the sun to melt.

Some metal bottles have a taste. Makes me wonder what stuff is leaching out of them. Specially the China made ones.