That seems to point directly to wireheading.

Pure hedon-maximization has that problem, yes, which is one reason why few people who've thought about the issues endorse that. But most systems of ethics include something that looks at least a bit like hedon-maximization. (Preference-satisfaction maximization. Maximization of things that usually lead to hedons. Maximization of hedons with some kind of weighting that values different kind of pleasures differently. ...) I don't think there are many people or cultures whose values don't say that it's generally better for a very hungry person to get a good meal.

Perhaps what you had in mind when talking about wasted consumption spending was spending on things much more frivolous than food. That's hard to assess, but the study we're discussing did distinguish a category of "temptation goods": alcohol, tobacco, and gambling. (I don't know why that particular choice of three.) They found that spending on these was not higher with cash transfers. (In their tables, I can find the entries for alcohol and tobacco -- spending on those appears to be lower for recipients of cash transfers, though the difference wasn't statistically significant. I don't see any numbers for gambling.)