He starts by giving more details about this event to remind the reader, reinforce its importance, and show how those involved in the event acted.
The lunch counter event at Woolworth’s in Greensboro took place in 1960 when people did not have access to the internet and social media. In that event, a group of young African Americans sat at the counter of a restaurant that practiced racial segregation and refused to leave when they were not served.
This was a protest against racial segregation and Gladwell reinforces that this protest was only effective, because people acted physically and didn't keep raising hashtags, or just complaining on the internet.
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