disgusting as it may seem, this mechanic could prove useful for decreasing nausea and other disease states during the game.
For example, having a high level of Nausea caused by an infection or an illness could cause the player to vomit, decreasing his level of nausea and increasing those of tension, sadness and hunger.
Moreover, the zombies may be able to smell it and approach the affected point if this happens in an uncontrolled manner.
Realizing that you have eaten something rotten, contaminated or poisonous may have a second remedy in addition to illness and eventual death, as an option in the toilets, sinks and showers it may be useful to force vomiting to save yourself.
It's disgusting but it's a mechanic that would add realism and alternative possibilities to the game