I guess that food makes a lot of difference in early game. Long run, I would say that food made me spend less money overall in my experience in Tibia (I mostly played under the level 100).
However, I see that in the long run, due to the more intensive hunts that nowdays high level will ususally make, food is just an annoyance. But you certainly are correct, it is better a little of advantage rather than nothing!
Let's all remember that food will help to boost other significant regenration items, like Boots of Healing or Ring of Healing! So it sums up with other relevant items, which makes more attractive feeding yourself constantly!