Nope, still no inventory combination in Sam & Max. It's something that's inherent to Monkey Island games, so it would've felt odd if it hadn't made it into those. But the Sam & Max games never really seem to need it.
I don't really get it. I never associated inventory combination with Monkey Island any more than with any other of the old lucasart games. Seems to me it's just part of adventure gaming as a whole, not of any specific game or franchise.
Not that i really care if there IS or not some item combination in season three, especially since the whole psychic powers thing seems more than enough to mess with and improve gameplay, and i sure agree with the "if it's not needed, why use it ?" approach, but i just don't really understand why it felt more "necessary" to you in MI than here.