Kasy has enough medical knowledge to patch up herself from most usual combat wounds, and can do some basic stuff for Turians, Batarians and to a lesser extent humans. There are a lot of things she can do fairly averagely, in terms of secondary skills shes a Jill of all trades.

And yeah, she can go with Marco and Tonka for food. Should be fun. Tonka can carry the equipment she buys. xD