The sign has invited a huge backlash online, even though the owner says it has been in the restaurant since the election.
The cafe's Yelp
and Facebook pages
were inundated with negative reviews calling the proprietors "liberal Nazis" and "beyond hateful." Some suggested a boycott.
"So, Cafe [8 1/2] hates Trump supporters enough to say they are not welcomed. Well, I wouldn't patronize a liberal hypocrite establishment anyways. I'm sure you can kiss a [s***] load of business goodbye," one Yelp reviewer said.
Others compared the sign to businesses denying black patrons service in Jim Crow-era America.
Some questioned how a business could be allowed to refuse service to Trump voters, but other businesses come under public and legal scrutiny for refusing to serve LGBT customers based on religious beliefs. (The bakery referenced in the tweet below was slammed with a huge fine
for refusing to make a wedding cake for a same-sex couple in 2013.)
The cafe's Yelp page is currently "being monitored by Yelp's support team," which often happens when businesses get media attention, and subsequently, waves of emotionally-charged reviews.
There were also those who supported the cafe despite -- or perhaps even because of -- the sign.
"Tried out this cool place," someone posted along with a pic
. "I hear it comes highly recommended amongst some circles."
The cafe's owner speaks
Robert Warner, the owner and chef at Cafe 8 1/2, told CNN affiliate KHNL that the sign has been up since the election
, and he didn't take it seriously.
"If somebody came in and said, 'Hey, I know you can't tell who I voted for, but I voted for Trump, would you let me eat?' I would say, 'Sure, if you're nice with me and I'm nice with you and you like my food, sit down, no problem,'" he said.
Even though he didn't think much of the sign, he still said he should be able to stand by its message.
"This is my place and if I don't want to serve a Trump person, I can do that," he added.
He said business has been good since the sign went viral, but he took it down on Wednesday.