A car is the perfect weapon for a radical revolutionary. You can't be out there with a knife and if you have a gun then you have an uphill battle to climb to try prove you feared for your life against a legitimate threat to your life but a car gives you deniable plausibility. "I was scared! I turned that way by accident!" It even gives you some degree of deniability of being there in the first place, you're just driving down a street ICE was operating in, how could I have possibly known!!! There's no suspicion in having one, the real brainfucked ones can even bring a kid or pet along for the rid., For revolutionaries, everything is a tool for the mission.
We already know these people communicate and organize with signal chats, I would not at all be surprised if there's printed literature these freaks put out about the effectiveness of cars as ramming weapons with all these amazing upsides.