It marked seven years since the Howard government passed the Marriage Amendment Act, instructing that marriage was purely the union of a man and a woman.

The rally came after the Prime Minister reiterated to the Weekly that the government did not plan to legalise same-sex marriage.

"We have, as a government, gone out of our way to equalise treatment for same sex couples under the law ... we've made sure that the treatment for same sex couples is the same as for married and defacto heterosexual couples," Ms Gillard said.

But thousands of people, of straight and gay, lesbian, bisexual, transgender, intersex and queer (GLBTIQ) gender expression, disagreed with the Prime Minister and marched to the State Marriage Registry to take part in mock wedding ceremonies.

Rory Shaw and Koby Drake, both 21, joined about 40 other couples who exchanged mock vows at the protest.

Mr Shaw, who grew up in Ballan, believes Ms Gillard contradicted herself.

"Finance Minister Penny Wong has just started a family with her partner. Gillard has congratulated them both and yet refuses to accept them as a legally married couple," he said.

"If the same-sex marriage act did become legal, I think that prejudiced people from rural fringe regions, such as Bacchus Marsh and Ballan and other areas, will realise that gay people are just like everyone else. Growing up in Ballan as a young gay male was difficult. "

Mr Shaw said there was a lack of services for GLBTIQ people in Moorabool and this contributed to discrimination and a lack of understanding from the community.

Mr Drake, founder of the Ballarat same-sex equality group Born Equal, said about 60 Moorabool residents had joined the group. Many wanted to speak to people with similar experiences from rural areas rather than join groups in Melbourne, he said.

The Weekly spoke to other members of the GLBTIQ community in Bacchus Marsh who wished to remain anonymous.

One woman said she chose not to reveal her sexual preference publicly for fear it would affect her business.

It has been speculated that the government will be under pressure to amend the Marriage Act at the Labor Party's national conference in December.

All state Labor branches apart from NSW have endorsed their support of marriage equality.