Why did poorly armed rebels adopt pikes?

Pikes as we well know had their usage in the time of Alexander the Great as part of the fearsome Macedonian Phalanx, and had a renaissance towards the end of the Middle Ages in the Spanish Tercio formation as well as the Swiss and Landsknecht Mercenary groups as a thick formation that could neutralize Heavy Cavalry.

However, after these periods, there was a general trend for poorly armed rebel groups to take up Pikes in their normally futile efforts to achieve their ends. Some examples of this are the Polish uprisings against the Russians, as well as the United Irishmen rebellion of 1798, Russian serf militia during the Napoleonic Wars, and the Confederates during the Civil War had plans to adopt pikes. There were even cases apparently during the American Revolution where militia units would be equipped with pikes because of a shortage of muskets and ammunition.

I understand that in cases of desperation, cheap weapons need to be adopted. But I question why pikes in particular were chosen. For pikes to work, they had always relied on a disciplined formation of men presenting a wall of sharp death in front of them and bulldozing everything in their path from sheer mass and discipline. In the event of a rebellion, the types of troops available would likely be ill trained and would rely on shock and numbers to win battles over better equipped professional forces. Why not just give everyone clubs and swords and go from there?

The pike is an unwieldy weapon that is of little use in individual combat. It can keep away cavalry, and in the hands of disciplined and trained men, plow over enemy formations. But against guns, it is of little value to be a slow moving formation without the ability to shoot back with much effect.

Basically, I am wondering why pikes were adopted in the case of rebellion when tactically, swords would probably be better, and likely no harder to find.