Thats how its designed. They are meant to be used after combat. in 2.5 years we have not used them, they are not worth the mats to make them (in the old game).
We only carried berries and aloe pots since the game started, now we have to redesign our heal methods.
The bandages are good for stopping bleeding takes it to cripple second level of encumbrance removes cripple just recently tried using bandages after playing since day one @Darthscully
Better cripple than bleeding out after some dancer sliced you up. I have taken damage not realizing it was bleeding ate some food and aloe potions run out of Sinners refuge and drop dead .
As it has been mentioned, this is the expected behavior for bandages in this current version of the game, although there will be some major changes to healing in an upcoming patch, more information below: