Really what it comes down to is the level of lazy.On the subject of creating character clones in general:
I don't see any reason that cloning should be looked down upon, especially considering how many times I've seen DM books say that it's okay to steal plots from films and stories. If stealing a plot is fine for the DM, then cloning a character is fine for a player.
A DM who just runs the Lord of the Rings without any modification is just as horrible as a player who plays a Drizzt clone. However, it is usually much easier to differentiate a storyline than it is a single character. I managed to run a series of adventures based on Knightfall (from Batman) and no one noticed the similarities until near the end, even the comic book geek.
You can draw inspiration from a character without making a clone, and I think the real question becomes where the line is drawn. I highly suspect this varies greatly from person to person.