Ms Syag, yashar kochech!
you were able to both help your friend and make a sale to the store! Consider an alternative – she buys from the store and you offer her money (as she seems to be getting free food somewhere else). This will be embarrassing her, of course. So, you fulfilled mitzva of tzedokah b’hiddur – and got an immediate reward in the form of chocolate.
More (free) food for thought – generally, food store did not suffer much, sale of groceries increased all over the country – at the expense of the restaurants. So, if your store suffered due to people getting federal free food, there are a couple of points to make:
1) I referred recently to Rav Huna who provided tzedoka in a similar situation by buying and sending away leftovers to lower market prices without making people dependent on charity ..
You described exactly the problem R Huna was trying to avoid – if you feed poor people directly, then you will destroy the livelihood of people who are still working productively and you may only increase number of poor people
2) having so many people relying on charity, and even a non-Jewish one seems to be a problem y itself. Rabbi Akiva suggests “make your shabbat like chol” but do not depend on tzedokah, and I think MB paskens the same way. Are we more permissive towards government charity?