That only works if you have clean water to mix it with and can sanitize the equipment.I just found nursing my baby extremely intimate. It's not something I could do for a stranger. I'd have no problem giving away the milk, but I don't think this was about nourishing this baby.
This was to make a statement.
There are a lot of hungry babies in the world, and donating formula(which she could afford to do) would be more helpful than breastfeeding one baby.