Venison stew is an extremely effective consumable item when used during combat, this is because only one stamina is needed to power attack. This results in the player being able to power attack every second for 720 seconds (although you cannot attack this fast). This gives the player a massive advantage during a fight.
This item is also easy and cheap to make due to the recipe being known by default and all ingredients are easily found or bought for low prices. Due to these reasons this item is very useful in the early game and in many cases outweighs the effects of regular stamina regeneration potions.