Gujarat's 'mobs' are not a random mix of Hindu activists. Rather, they are the designed outcome of the RSS-VHP-BJP strategy to weaken Dalit-Adivasi activism and turn it against Gujarati Muslims.
One of the most cruel ironies of the violence in Gujarat is the significant participation in that state-supported anti-Muslim pogrom by the 'subaltern' classes of Hindus, in particular Dalits and, to an extent, Adivasis (indigenous tribal people who are not quite Hindus). These are the very same forces whose self-assertion in the 1980s was seen as a major threat by the upper caste Hindus who proceeded to crush it.
In fact, it is impossible to understand the strong roots that Hindutva has struck in Gujarat's society and politics and the success that communalism has come to enjoy in that state without understanding the origins of the consolidation of the rule of the upper castes, particularly of Brahmins, Banias (traders), and the patidar (upwardly mobile land-owning) Patels.
These origins go back to the formation of a social coalition known as KHAM (Kshatriyas, Harijans, Adivasis and Muslims) conceived of by the left-leaning Congress strategist, the late Jinabhai Darji. The KHAM strategy, based on the "core minorities" and the lowcaste groups known in Gujarat as Kshatriyas, was itself a part of a new political mobilisation that Indira Gandhi tried to evolve in the late 1970s/early 1980s. This sought to distance the Congress from its dependence on uppercaste Hindu groups such as Brahmins and Marathas. It represented a major attempt at "political engineering" based on the common interest of these groups in gaining access to political power from which they had been excluded for long decades, if not centuries, by the "twice-born".