In the video, shoppers and staff members came to the woman's defence, with one woman even standing in front of her as a physical barrier.
"He has no right to be doing what he's doing," said the woman. "You shouldn't be ashamed of feeding your baby. This is a beautiful moment right now."
In a follow up post, Maher says she has received an "outpouring of love and support" since uploading the video.
"Loved ones, acquaintances, and complete strangers have posted, re-posted and linked to our story," she wrote.
"I have received several hundred [Facebook] messages in support of me and my right to breastfeed. Mamas have opened up and told me their stories, they've said they stand by me, they understand what I went through because they too have been in public with a screaming baby.
"Some run home and deal with the screaming baby, some hide in a bathroom, some sit down and cover up with a blanket, some sit in a hot car. This is all in fear of the reactions we get, whether it is a dirty look or the extreme situation that I endured yesterday."
Maher says she will continue to breastfeed her baby in public.
"I choose to openly breastfeed my child when ever and where ever she happens to be hungry," she wrote.
"I choose not to cover up because I am not ashamed of what my breasts are intended for. I stand with all mamas breastfeeding, bottle feeding, covered or not. It is hard enough being a mother, period. We need to build new mothers up not tear them down.
"Let's be kind, let's be gentle. Let's normalise breastfeeding, because that is exactly what it is, normal, nothing more nothing less."