Not because the capital spared from denied meals (or production thereof) are going directly towards yachts, but because the capitalist mode of production requires the threat of starvation to force us into unfavourable compensation for our labour.
Really, we could easily do both at this point (and more), but since greed knows no limits, there is also no limit to what pain the capitalist class will impose on us in order to extract surplus value.
We already produce enough food for a billion more people than what exists, but still around a billion live in starvation to deter the rest of us.