A Facebook post showing a copy of the hate mail sent to Restaurant Platon has received more than 12,000 Facebook "likes" and been shared more than 3,000 times since restaurant owner Christina Maria Dora published the letter on the social media website on Tuesday evening.
Fueled by the ongoing debate over Greece's bailout by European creditors, an anonymous writer targeted the family business which has existed for over three decades.
"YOUR new Greek government is brazen, impertinent and behaves like a mob of crude, mannerless jerks," the writer begins, before accusing Greece of "extorting other hardworking countries" in order to continue its "lazy and comfortable lifestyle."
"Pay taxes...why? Work...why?" the letter says, "Laying in the sun is much more comfortable, especially when others pay for it."
"As long as this government continues to sordidly disparage and offend the particularly hardworking and economical Europeans and Germans, we will no longer be buying anymore Greek goods, nor stepping foot in your premises," the letter promises. "Go back to your own corrupt, rotten and totally incapable dirty Greece."
In response to the letter, Dora said that it was "a shame after 31 years to feel unwelcome." "We speak and write German and pay taxes like evey other German citizen. We have created jobs and built our life here," she added.
Amid negotiations with European creditors in recent weeks, the German press has seen a significant increase in Greece's presence across its headlines.
In an interview with Deutsche Welle, Dr Pawel Tokarski, an academic and researcher at the German Institute for International and Security Affairs (SWP), said the image of Greece in German media is very one-sided.
"The German media doesn't like to show the real situation in Greece - they like to paint a very black and white picture," Tokarski told DW, adding that this "damage" had now reached society.
"It is the job of the government and the media to repair this damage and bring German and Greek society closer."
Tokarski maintained, however, that these negative opinions are only among the minority of German society.
"German society in general is very tolerant," he said.
The expert in European affairs warned, however, that the negative feelings could re-emerge in the German press when the current four-month bailout extension comes to an end.
"The problem is that the negotiations with Greece are not over and we only have some breathing space. When the new talks start … the simplistic pictures in the German mass media can come back," Tokarski said.
Similarly, chairwoman of Düsseldorf's German-Greek Association, Catherine Yannidakis-Hahne, told DW that the German press has led a huge campaign against Greece.
"One isn't informed objectively here. Instead, one hears only the sensationalism of the press; therefore, I don't take such things seriously anymore," she said, adding that the family-run restaurant in Düsseldorf has "absolutely nothing to do with Greek politics."
A hashtag launched last week on Twitter showed, however, that Germany is already taking a stance against the media's biased representation of Greece. #NeinzurBild - meaning 'no to the Bild' - began trending last week after Thursday's edition of the German tabloid Bild printed a huge headline reading "NO! No more millions for the greedy Greeks."
Popular German culture show Circus HalliGalli also left viewers with a surreptitious message during the closing credits of Monday's episode by displaying a "reminder" which read: "Pro Greece! Pro Europe! Against dumb populism!"
Following the predominantly positive response on social media, Doras said on Wednesday that the family was "overwhelmed" by the thousands of comments posted by Facebook users.
"We are Europeans and as Europeans we must stick together!" said one user.
"I only know nice, hardworking, diligent Greeks," wrote another.
Dora said the supportive messages had shown Germany's openness towards the Greeks.
"We are very fortunate to live in Germany and feel at home here," Dora said.