I used quotes because I was quoting my flatmate. She said their demeanor was not welcoming at all, and it felt very aggressive. I kind of wish I was there just so I could have told them what I thought, but spilled milk and what not.
Not saying this is the case, but it occurs to me... that would be a good way to sabotage the start of an union. Just send some aggressive people posing like members of the union.
It is, and there's evidence that has happened in the US.
The Pinkertons have been busting unions for over a century - they have pretty much explored the full range of options for worker suppression available to capital.
False flags can be a powerful tool (but becoming less so, as surveillance makes deniability harder).