The real issue here is that they weren't "Jacobin" mobs. The Sections of Paris, the local neighbourhood organisations that provided much of the manpower for sans-culottes violence and pressure politics, were never entirely Jacobin. They were their own groups with their own motivations and politics. One of the reasons that Thermidor is successful, and that the regime is less pressured by the crowds of Paris post fall of Robespierre, is that by Thermidor Robespierre and his group had lost the support of the Sections. That's why, on the night of the coup, he sent dozens of messages to the leaders of the Sections asking them to support him - he knew they would tip the balance in his favour but they failed to turn out for him.