food issues and adopted stray

Hi everyone I am new here and have a question. I have 2 female cats that I have had for 5 years. Recently(2 weeks) a stray(and quite possible the sweetest little guy ever) has found his way to my house. The poor little thing was sooooo skinny he couldn't even meow or barely keep his balance. Of course I have fed him and he seems to like staying out in my mud room so he has complete access to the outside and a nice comfy place to sleep. After a week he most definately wasn;t going any where so I took him to the vet, all was well with him except for he is an old man and can barely see (about 5ft tops)and is partially deaf.(He was in pretty bad shape when he arrived end of nose ripped off and missing one of his toes ...big hole and bleeding and infected, and big cuts near his eyes and ears) so I don't know if he is this way because of a fight.
Anyway, he will eat and eat and eat and eat. He will run right in the house and go directly for my other 2 cats bowls and eat all of their food until its gone and the still want more, even after I have feed him from his own bowl. He was wormed at the vet, but is it possible that he could have a tape worm or do you all think it could just be because he went with out for solong, he is afraid he will not get enough. I am keeping him on a regular feeding schedule with my other 2. Any opinions, thoughts or suggestions would be helpful.

Regular feeding schedule sounds good. They do think they need to eat everything in site - they are afraid that they won't see food again for quite some time. Hopefully after he understands that he doesn't have to owrry about food ever again - he will slow down a bit.

My Andy, for the first several months would eat until he threw up, and then eat some more. Now he understands that his food supply is endless and only occasionally pigs out.

Welcome to the forum!

Thats what I was thinking, hopefully he will realize that I will never ever let him be without. He was obviosly someones cat , because he is very friendly, he knows what a door nob is and how is used (little stinker), and he listens very well..you just have too be very near him so he can hear you. EXCEPT, when it come too food..he turns into super possesed man and completely ignores us when we tell him no and to keep away from the other cats food bowls. I would like to be able to let him in the house more often and for longer periods of time(although he is perfectly content outside), since he is old and has some issues and eventually I don't think I will be able to let him outside at all.

I always feed the strays I get in extra because usually they need to gain a little extra weight and because I don't want them to feel deprived. Then after a couple weeks of adjustment I would feed less. It just takes time.

Did they do blood tests? He may have a treatable condition called hyperthyroidism. It can cause excessive eating and skinniness. It would be worth it to have the test done to rule it out if nothing else. I found an old kitty boy last year, and he has it. He is such a sweety.