Federal Sydney MP and Environment Minister Tanya Plibersek, NSW Police Minister Yasmin Catley, Independent MP Alex Greenwich and Sydney Lord Mayor Clover Moore were among those who filled Green Park in Darlinghurst on Friday night.
The bodies of Mr Davies, 29, and Mr Baird, 26, were found inside surfboard bags at the fence line of a rural property in Bungonia near Goulburn, about 200km southwest of the city, on Tuesday.
On Friday evening people sat on the grass and silently watched as a slideshow of the two men played on big screens alongside a soundtrack of Shania Twain, Lionel Richie and Coldplay.
The slideshow depicted two lives well lived with images and video of each of the men on holidays, career highlights and dancing at parties.
In a statement friends of Mr Davies said his smile lit up every room.
"We hope he will not be remembered for the tragic events of the last week and a half, but for his beautiful soul, adventurous spirit, and the joy he brought into all of our lives," they said.
Friends and colleagues of Mr Baird said he was "the life of every party".
"His life-loving attitude was infectious and he was pure joy to be around," they said.
"That's what we want to carry with us, how lucky we were to know and adore him."
NSW Police officer Beau Lamarre-Condon is charged with murdering Luke Davies and Jesse Baird. (HANDOUT/NSW POLICE, STUDIO 10)
Network 10 presenter Narelda Jacobs held a candle before signing the condolence book.
NSW Police officer Beau Lamarre-Condon, 28, is in custody charged with murdering the couple at Mr Baird's home at Paddington in inner-city Sydney on February 19.
The Friday-night vigil was organised with the permission of the couple's families.
It took place on the eve of the annual Sydney Gay and Lesbian Mardi Gras parade, where organisers are expected to recognise the couple.
Mardi Gras board co-chair Brandon Bear said the LGBTQI celebration will be a more sombre event than usual for some people.
"Everyone brings what they are going to bring to Mardi Gras ... if you do come along to parade on Saturday, there will be a space for you, we will hold that space for you and you can be part of our community in that space," he said on Friday.
Hundreds of people attended a vigil in Sydney for slain couple Luke Davies and Jesse Baird. (Bianca De Marchi/AAP PHOTOS)
Detectives allege Lamarre-Condon's killing of Mr Baird with his police-issued gun was a premeditated attack after a months-long campaign of "predatory behaviour" towards the man he briefly dated.
Mr Davies, a Qantas flight attendant, was allegedly murdered because he happened to be in the Paddington property at the time of his partner's killing.
Mr Greenwich said his office, along the parade's Oxford St route, had been overwhelmed with community distress.
"I did not know Luke or Jesse, but the memories and stories shared with me show how these two young men brought positive energy and goodwill with them everywhere they went, " he said.
Mourners leave messages during a public vigil Jesse Baird and Luke Davies. (Bianca De Marchi/AAP PHOTOS)
Qantas will honour Mr Davies on its Mardi Gras parade float, while the AFL is expected to announce a tribute for Mr Baird, who umpired 62 games including two finals, in coming weeks.
NSW police officers will march in the parade out of uniform after reaching a compromise with organisers, having previously been uninvited after Lamarre-Condon was charged.
Police Commissioner Karen Webb did not attend the planned vigil as she did not want to interfere with the grief of mourners.
She will attend the Mardi Gras parade on Saturday.
