They hopefully won't but the threat of arrest, even if they won't be indicted, is definitely enough to have a dampening effect on people exercising their rights. At the same time I wouldn't be confident in the courts protecting your first amendment rights [1] especially given the current court.
[1] https://en.wikipedia.org/wiki/Schenck_v._United_States (Note: this case has been overturned, but it took 50 years)