When in spectator mode, furnaces can be used whereas crafting tables cannot. This also happens with chests.
MC-46451
Spectators can use furnaces but not crafting tables.
Resolved
Works As Intended
0
Players in spectator mode can look into tile entities that other players can interact with. The crafting table is client-side, so it would be pointless to be able to view it. Essentially this is intended, so players in spectator mode can see how other players are interacting with the world.