[pringle]

Very valid point, most petitions are in fact a sham.

But given that exercises like these are incredibly important to the viability of organizations -- organizations whose mission/cause/work you presumably agree with -- wouldn't it be pretty bad if everyone just stopped taking part in these?

The bottom line is that these petitions work and allow organizations to carry out a mission that their members do in fact support, whether or not the petition is a sham. It's definitely a problem that they have to resort to doing crap like this, but until there is a better way, I don't see what else they can do.