I personally think that most classes with the exception of mages, and possibly necros should only get that kind of ability. Classes like a cleric, shaman...their forte is something else that they are known for, like healing, or doting, or whatever else, not summoning, therefor it should be a bit harder for them to summon food and water. Your right, its not as convenient, but I think thats ok considering what their other strong points are.
Mages do get a 5 at a time summoning for food and water later on though. Miraculous Food and Water.