Corporations don’t willingly give up money. In circumstances like 1 and 3 they’ll more likely just say “thanks for making line go up more” lol. COVID imposed some supply issues that I would assume are mostly mitigated by now, but I haven’t seen costs decrease, only increase–so now we have record profits in many contexts. Subsidies can sometimes help, but it seems to me that the most effective subsidies (in terms of lowering cost) are those with significant, more powerful corporate players downstream (e.g., corn in the US) rather than those purchased by individual consumers who have comparatively little power.
I don’t know that 2 is necessarily quick, but competition can indeed lower prices if a competitor can actually survive against the behemoths in their respective markets. In those instances, corporations can try to shape regulation to squash the upstarts while leaving the big players alone.
I’m not sure that government really has the ability to lower prices in a way that isn’t somehow perverted by large corporate entities given the power they have.
I thought “on line” was an Eastern US thing; never heard it in the South, Midwest or West Coast.