> tobacco companies and junk food in schools
Bear with me, I think these are actually two examples of net good (potentially) done by lobbyists, where their (admittedly uncaring) business incentives end up standing up for what people want.
Tobacco and junk food are big targets for the "protect us from ourselves" crowd who think they should dictate values to other people. Just because they aren't good for you, government shouldn't be telling people what to do. Luckily (and I mean this, it's essentially a coincidence) the incentives of tobacco companies and soft drink manufacturers or whatever align with giving people what they want, so ordinary people who would otherwise get pushed around by controlling political types (for their own good) get an unexpected ally.
I've seen this with covid too, few stand up for people who just want to do their own thing and not get pushed around by people who want to impose their values of maximizing for health (pretending to) at the expense of all else. The only groups with the clout to stand up to health officials mad with power end up being lobbyists for companies that are losing money hand over fist, and the interests align.
I'm not saying it's utopian, but for better or worse, they end up providing a much needed countervailing force against what might otherwise be a march to some technocratic hell hole where people can't make their own choices because someone knows better.