That's valid as long as there are only two choices, but a more accurate analogy would be that we don't really care what people eat as long as they eat fewer tac

That's valid as long as there are only two choices, but a more accurate analogy would be that we don't really care what people eat as long as they eat fewer tacos. You could subsidize burritos, but that's less effective for people who would have had enchiladas as their second choice. In fact, some portion of people who would have bought enchiladas anyways might end up getting burritos because they're now cheaper, and the government foots the bill for no good reason. Another factor to consider is that the subsidy must be paid for by somebody, so you end up needing to raise the money through taxes anyway. This means that ultimately you are raising net taxes on everything that's not subsidized. With all that being said, you're completely right that subsidies are an easier sell. They have an enormous advantage: you can seperate the spending / mechanism of action (which people love) from the taxes that pay for it (which people hate). Taxes on bad things inherently tie the two together, which makes the marketing harder. Additionally, the benefits of subsidies are concentrated while the costs are diffuse, which makes it easier to build a strong voting block in favour of subsidies.