Many reels came in boxes but some of the finer, more expensive reels came in cases.  Most vintage cases were made of leather and would hold a reel snugly in place while protecting it from the elements.  Big game reel maker Arthur Kovalovsky made solid cases out of Micarta, a material used for insulation.  Kovalovsky's cases were bulletproof affairs that could withstand a drop from a two story building.

Vintage Fishing Reel Cases