Main said the messages of care and support for the Milnes have been constant since she put up the post on Thursday night.
The Milnes have been regular market stallholders, selling their popular baked goods, and Main said other traders will want to support them.
"They are well-loved in Whanganui and have a very caring community in the Delhi village."
The Milnes' neighbour, Ron Fisher, said he was feeling devastated for them.
"I was the first person to arrive there after the fire started and felt helpless that there was nothing I could do," he said.
"It was so quick and I'm just grateful that John and Miranda are still with us."
Fisher was planning to start a Givealittle crowdfunding page for his neighbours.
"If people go to the site and search for John and Miranda Milne they should find the page," he said.
Koha Shed manager Sherron Sunnex has offered the Milnes a private shopping trip to collect things they might need.
"We have furniture, kitchen things and linen so they can come and have a look when they are ready," she said.
"We know from our experiences after the flooding in 2015 that insurance claims can take a while to process so we're ready to provide things that will help in the immediate future."
John Milne said he was thankful that the Whanganui community was willing to be so supportive.
"I'm feeling a bit vague at the moment but we're very appreciative that people are wanting to help," he said.
"Whanganui people are very kind. I want to thank the firefighters who attended as well. They did their job with a lot of compassion and kindness."
