I feel like this is a result from the things that are going on behind the scenes - the riders do not feel like they have enough influence, like their issues are taken seriously enough, like they are heard. They feel helpless and like they don't have the power to change anything, especially with the increased economic pressure (this season). But they don't dare to say anything because their contracts might be in danger. Then the dynamics lead to small things bringing out a feeling of "we are not going to take this (anymore)", and they end up protesting against minor situations, also too late (and not as one).
At least that's my theory, as that's what happens in other areas quite often as well. The protest then does not look to be taken seriously from the outside.
Edit: Ah, and often that happens when actually something is changing, when people are starting to get more influence, when their issues are heard more. This happening often leads to an even strengthened sense of injustice/not being taken seriously enough, because before nobody talked about it and everybody told themselves that there is no issue, that's just the way it is.