There are a few ways to spin this; perhaps LeBron is just being nice to engage in damage control. Plus, while Zydrunas' words might seem a little cold, at least he's willing to admit that basketball is a business in which rival teams fight to come out on top over all competition. At least he's being honest about his feelings, unlike the devious James.
Except, if we're to commend Ilgauskas for telling the truth, then we also must admit that the affection Cavs fans still feel for him is a bucket of lies, too. Zydrunas is ultimately playing basketball to win and make money. So while the Cavs fans can appreciate his time with the team, they shouldn't act as if he has a kind heart unmatched by anyone who's ever worn the uniform.
In the end, Ilgauskas could be just as cold-hearted as LeBron. There's no doubt that James handled his departure from Cleveland poorly, but the difference in the reactions towards him and Ilgauskas can probably be explained best by the gap between their respective abilities. When you get right down to it, fans hate on the best player who left, not the worst person.
This really isn't all that hard to understand. One player quit in the playoffs, made a spectacle of leaving and stabbed the city in the heart on national television. The other player worked his tail off, signed somewhere else like a normal free agent and placed an ad in the paper thanking fans for their years of support.
No one hates Z because they don't feel that he disrespected them at any point in time. Sure, talent has something to do with it (losing a past-his-prime center is easier to stomach compared to the two-time MVP) but if you ask any (sane) Cleveland fan, they'll tell you it's not that LeBron left, it's that he rubbed our faces in while doing it.
This isn't hard.