There are two aspects to the question. The first is whether a cat owner can put down one food bowl for two cats which they amicably share. The second is whether cats will altruistically eat from a single bowl and then push it towards another cat. The other cat then eats from the bowl and pushes the bowl back, and so on. Or they wait and take turns.
Cat owners do put down one bowl of food for two cats but all the experts say that each cat should have their own bowl of food and water. This avoids possible stresses. You will see videos online of cats being bullied over the use of a food bowl. It is not uncommon in multi-cat households for one cat to bully another. This needs to be avoided for obvious reasons. The same rules applies to litter trays. It should be one litter tray per cat and one extra according to Jackson Galaxy. The video below is a classic example of feline bullying and/or dominance over a resource: food.
But there’s no doubt that domestic cats will share a food bowl without difficulty provided they get along. And sometimes they go further than this. There are videos on the Internet of cats actively sharing the food or water in one bowl. One cat drinks from the bowl and then pushes it towards the other. The other cat then drinks from the bowl and pushes it back. They do this quite quickly and rhythmically. It looks very much like reciprocal altruism.
Note: videos on this site are typically made by people other than me and held on YouTube servers or the servers of other businesses (not the server storing this website). Sometimes the videos are deleted at source which stops them working on this site. If that has happened I apologise but I have no control over it.
Reciprocal altruism does take place in feral cat colonies when queens help raise each other’s kittens. This helps in mutual survival. It is not entirely altruistic, therefore. There is a purpose behind it which is personal gain but the gain is obtained through an act of apparent altruism.
Perhaps, then, the sharing of food bowls has the same purpose? It maintains the peace and both cats get their food. True altruism is a demonstration of a selfless concern for the well-being of others. There should be no personal gain in the process. It is quite an elastic concept, however. At the end of the road, which is sometimes in the distant future, there may be a reward for the altruistic animal or person.
Another aspect of the undesirability of making cats share food bowls is that it goes against the grain of their innate behaviour. This is because their wild ancestor eats alone. Therefore the natural state of play is not to share bowls. That said, we know that the domestic cat has adapted to sociability over about 10,000 years of domestication. They can get along very well in homes. This solitary characteristic of their personality is less well-defined in the modern domestic cat.
However, the trait will vary between individuals and therefore in the interest of harmony and the avoidance potential of aggravation separate bowls is the order of the day.
P.S. There is a health aspect in sharing food and water bowls: it is a potential source of transmission of disease in the saliva of cats. This is too be avoided or minimised.