Some have likened it to "bathing in each other's dead skin cells'' but others can't see a problem with it.
So, would you share a towel with your significant other? According to Kidspot, the consensus is a hard "no".
"I don't use the same towel either," one person wrote on Mumsnet, as she'd seen her partner "floss his butt with the towel".
Another wrote that they wouldn't share towels even in an emergency.
Aussie mums had more varied responses, with one admitting "we have shared towels".
One said she'd share as long as the towel was dry.
"I'm okay with sharing towels so long as there's enough gap between use. Like if someone has a shower at night I need my towel dry by the next morning. Damp towels gross me out."
One said there was no way she'd ever share towels.
"NO. You still lose skin cells. It even kills me if a visitor accidently uses my towel instead of the hand towel to dry up after the loo."
And when one pointed out that you still lose skin cells in bed, she replied "But I am not rubbing them into my face".
One mum asked the key question: "Do you dry your bum or your face first?" but that's a whole other topic.
But what do the experts say? In 2018, University of Sydney senior microbiology lecturer Dr Nick Coleman spoke to Triple J's Ben Harvey and Liam Stapleton and tested their towels.
Harvey admitted he used a communal towel in his parents' bathroom that gets washed once a week.
Coleman told him: "The extracted liquid [on the towel] is like a horrific soup of dead skin cells and bacteria and lord-knows-what. Ben's was way, WAY more gross. Like, it was disgusting. I was pretty shocked actually."
Kidspot recently asked the controversial question about whether it's okay to share a toothbrush with your partner.
And although most responded with a hard no, a few admitted they didn't have a problem with it.