Yes, a politician did actually say this. In 2017.

Over the course of the next few months, the people of Australia will be able to take part in a postal survey that will determine whether or not the country will follow in Ireland’s footsteps and legalise same-sex marriage. As it did before the referendum here in 2015, the issue has been the subject of plenty of debate Down Under, not all of which has been what one would call reasoned. Far from it, as it turns out, in the case of Liberal Senator Eric Abetz. A long-time opponent of same-sex marriage, Abetz conducted an interview this week with Buzzfeed in which he put forth a quite ridiculous reason why it should not be legalised in Australia… because someone might end up marrying the famous Sydney Harbour Bridge as a result. In response to his claims that the legalisation of same-sex marriage could lead to humans marrying inanimate objects, the iconic Sydney Harbour Bridge was put forward by Buzzfeed as an example of the type of inanimate object that might fall into that category. Asked if someone might end up marrying it if same-sex marriage was made legal, Abetz responded: “Why not? Why not.

“Look, I would like to think that that is taking the argument to the limit, but the issue is if we are judging this solely on a person’s view of what love is to them, and people [ask] me, 'how can you judge somebody else’s love?', then I think you’ve got to accept that love is love and that’s the slogan. “Having said that, whilst we very much believe that marriage has something to do with love, the marriage act does not require it...”

Abetz was then asked if he was making a comparison between the love between two people in a same-sex marriage and the love between a person and the Eiffel Tower (which an American woman held a commitment ceremony held in 2007).

"The sad thing is, I’m not doing it,” Abetz responded. “There are people that are actually saying they want to marry the Eiffel Tower. There are people that say we want a threesome marriage, and 'who are you to judge that marriage should only be between two people?'” “I think our society would not accept people being able to marry the Eiffel Tower, but if you just limit it to people then there are issues in relation to polyamory,” Abetz added.

A voluntary postal vote on same-sex marriage will take place in Australia from September to November of this year.