My cat constantly meows for food even when I've fed him. Any advice on what to do?

I have really tried to be patient with this situation but it's starting to drive me crazy. Our kitten was about 3 months when we got him, he is now 6 months. It started when I placed his food bowl in the kitchen and fed him dry kitten food, after an hour he would meow non stop for food. So I started feeding him wet cat food but a week later he was back to the same pattern so I gave him a little more food. This didn't help all he wanted to do was eat more, he only looks for me as the person to feed him even though there are two other people in my house who have fed him. Whenever walk towards the kitchen he will beat me to it and sit next to his food bowl, when I open the fridge or pour a bowl of cereal he will run into the kitchen thinking that it's time for him to eat. In the middle of the night if he sees me getting up he runs to his food bowl and meow loudly. Fixing lunch and dinner is the same, he sits in the kitchen meowing and staring at me. At the dinner table he will quickly jump on the table and the snatch food off of our plates. It's getting worse because he is now starting to dig through the trash for food. What is causing this behavior? Why is he so obsessed with food? I have owned 4 cats in the past and none of them behaved like did this.