And true, some cats just binge and throw up their food because they've
learned to eat fast on the streets before some other cat gets it, or maybe
because their stomachs and intestinal systems have been messed up by the
garbage they've had to eat while out there on the streets, or by parasites
they've had in the past. If he has a good weight and doesn't lose weight,
its not necessarily a problem (except to the person who has to clean it up!).
I find that feeding such cats smaller amounts more often may help.