But a Melbourne woman was denied the two-for-one offer when she went to Grill'd in Point Cook with her partner because she was female.
"I was impressed that Grill'd would get on board and give away burgers for a worthy cause and it had a catchy name, easy to remember when it was on," Melanie said.
"I ordered at the counter and asked if I could use the MAYEIGHT!! offer. Although the waitress was very pleasant she said as it was for men's health it was only available for men and although I was eating with a man the offer was not available to me.
"I ordered anyway as my interest in men's health is not limited to free food but it did put a dampener on for us trying to figure out why a day for health was not inclusive.
"I was disappointed - not that I didn't get a free burger as I was happy to pay for the burger or would have been even happier to pay for it and that money go to the cause, but disappointed that as a woman I can't be considered a mate or a support for my male partner or male friends."
But a spokeswoman for the Movember Foundation said it was a misunderstanding and the offer was open to women as well.
"It was open to women as well. Unfortunately the customer was given the wrong information by the staff member, and for that we apologise," the spokeswoman said.
"While we were encouraging men to catch up with their mates on May 8, the offer was also open to women."
Grill'd has also offered to get in touch with Melanie to make up for the mistake.