I can see where Vlam is coming from. In game canon, we didn't see that much of their relationship, AND I don't think they would be hugging each other constantly. However I did intent for the hugging to happen much later when they did become friends. Reason why I believe them to be friends is because Alf did mention that him and Munch were "tight" http://www.oddworld.com/2013/10/dear...-karate-chops/
so I just assumed that Abe and Munch are too. Abe does call Munch 'buddy' most of the game. According to Alf the only dislike they have about Munch is that he smells like fishes(and also that he's too clingy, but I'm not sure about that).
But honestly, I would've loved to have seen them not get along in the beginning and watch how it would develop from allies to friends. But I guess we do get a little bit of that in the Munch's Oddysee good ending: Munch IS REALLY pushy to Abe about getting the gabbiar, however later when he does have the gabbiar (and has calmed down a bit) he does thank Abe for what he did. Abe seems really surprised by this, maybe he wasn't expecting something like that from Munch? They are kind of awkward after that tho.