I liked Kirby being able to make suicide kills, but there's also some advantages to taking the Kirbycides out. I want to say they did it to make it less frustrating for everyone. I played Melee with my friends a few days ago, and I played Kirby almost every match. Now, my friend is usually a really calm guy, but something about Kirby brought out the worst in him.
In one 4 stock match, he played as Shiek and took out my other friend friend fast (Home Run bat smash x 3, kinda surprising really.) He switches to Zelda, knocks me off the stage, and tries to follow up with her ridiculously strong aerial kick (I forget if it's fair or bair). I know this, so I swallow her in the air and just plan to fall into the abyss. As soon as I do this, he ends the match (which really surprised me.) Now, my other friend thinks me swallowing him was ok, but the Zelda player disagrees.
I won several matches with kirbycides (and a flatzone match with swallow and spit ^^), and he starts saying stuff like, "is that all you ever do?"
Then, after another match where I win with a Kirbycide, he shuts the Wii off in frustration right as I throw him off! It's really not like him to do that.
So yeah, even though I thought it was ok, he kept callling it cheap and stupid, while my other friend thought it would be ok if the only suicide was a swallowcide. But I will miss grabbing someone on the last stock and saying, "Goodbye!" right before I send us both into the abyss.