No, that is not always necessary.
Unlike a billiards or table football table, the ball does not have to roll.
Football tables: Only our football tables must be placed level!!
Ping pong tables and foot volleyball tables: We place these with the bottom in place. In this way, the height of the table, measured relative to your feet, is the same on both sides. This is certainly an advantage if the children play the game "Around the table". They then do not have to adapt to a height difference. After all, if the table were level and the floor sloped, the table would feel higher on one side compared to the other.
Benches and picnic sets: In principle, these are all placed with the bottom. Our driver always ensures that the products cannot 'wobble'.