They were following the suggestion of a sitting senator to get in the face of some congresspeople.
Then there's this lunatic
Rep. Maxine Waters (D-Calif.) is calling on her supporters to confront Trump administration officials and staffers in public amid widespread backlash to the President’s zero-tolerance policy on illegal immigration.
“Let’s make sure we show up wherever we have to show up,” Waters told a crowd in California over the weekend. “If you see anybody from that cabinet in a restaurant, in a department store, at a gasoline station, you get out and you create a crowd, and you push back on them, and you tell them they’re not welcome anymore, anywhere.”
https://time.com/5320865/maxine-waters-confront-trump-staffers-family-separation-policy/
You people who support the above two lunatics should take a long look in the mirror.