They are apparently (lower) middle class - or at least those who started it. Hit by both increasing fuel/Petrol prices and taxes leaving them less and less money in their pockets. Basically it'sthe folx that keep the country going. And then you have a pretentous, condescending president in power who's "base" is the 5% of the richest in the country. Will lead to frictions sooner or later.
Of course, by now that amorphous movement has been highjacked by several radicals (both from the right and left).