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Answer: People didn't cross picket lines to show solidarity in an attempt for better wages, better working conditions and various other things that would or could make their lives better.
Explanation: Back in the 50's and 60's when unions were very strong, you were considered a "scab" if you crossed a picket line. You took a chance of being hurt, harassed by other strikers and you showed you were not a team player.
Answer:
On December 1, 1955, Rosa Parks, a black seamstress, was arrested in Montgomery, Alabama for refusing to give up her bus seat so that white passengers could sit in it. ... Following a November 1956 ruling by the Supreme Court that segregation on public buses was unconstitutional, the bus boycott ended successfully.
