Because people’s perception has a positive bias. Rationality corrects that bias towards neutrality, which if you place on a cardinal axis moves it left towards negativity.

Condom.

Improve your lighting. There are guides to customise filters for food pics that enhance saturation, brightness, exposure and give a small vignette and fish-eye lens to improve the quality of the pic.

Edit: Oh nevermind… Clicking on the picture completely changed the saturation and brightness…

Eat calorie-negative foods like anti-pizza and anti-lasagna.