naturally these groups existed, despite typical anarchist propaganda of the "we are everywhere/everyone" variety and the fact that they did inspire a few imitators, there were distinct groups of people who carried out these actions in the 90s and early 00s, and most of them are in jail now. their "strategy" - to the extent that these weren't acts of principle carried out as ends in themselves - was the idea that they'd inspire a mass movement (which obviously failed to materializ), since there is no way a few scattered handfuls of people carried out sporadic arsons could oppose the massive forces of progress and make the kinds of vast changes they were talking about.
ironically, there is an ecological mass movement brewing, and it is the mobilization of disaster capitalism or even green socialism - the coming ecological police state. there was a great piece i read years ago contrasting the green capitalist narrative with radical environmentalism: "you, individual, can buy fluorescent lightbulbs, compost your kitchen scraps, recycle your cans etc" vs "you, individual, can ride bikes, eat trash, and even punish those who are ecologically 'bad'".... it still adds up to the same sorry state of affairs...