Of course macroing isn't "harmless", but more often than not, it is an indication that a particular game mechanic is just boring, however. In this case, the main problem is neither how straining it is to eat 30 mulberries, nor that it can be macroed, but the fact that you need to eat 30 mulberries to begin with, and that you need to do it 20 times per day.
We fully plan to rebalance hunger values and the hunger drain, and the FEP values of food so that you'd need to eat a lot less, but to do so right now would probably clog up the economy of the game (since food would be ridiculously abundant), and that part is harder to fix. I might consider adding a "Feed" option until then, but it just gives me weird images inside my head. (*Imagines a Hearthling wrapped around a tree, leeching sap out of it*)