Please don't compare Hanukkah with "Kwanzaa." Hanukkah may be relatively minor compared to other Jewish holidays, but it's legitmate religious expression, unlike the invented, bogus "Kwanzaa."
Hanukkah is certainly not in the same league with Passover or even Rosh Hoshanna, which could be comparable to Easter and Christmas in importance. But I didn't mean to imply that it was a made up holiday; however, its prominence in the US is basically seen as a counterweight to Christmas.
There's nothing wrong with that, but that doesn't mean that a small group of citizens gets to knock out a symbol of a traditional holiday celebrated by the majority. And if the rabbi really felt the Christmas tree was some dread symbol of Christianity - which it really isn't, but has become a cultural symbol of winter, and in fact is objected to by many Christians - he should have approached the airport months earlier and discussed this, rather than storming in with his attorney.
Incidentally, the Lubavitchers have done this elsewhere in the US, most notably in New York (where they displaced Christmas symbols and got their menorah, while Christians - the majority of New Yorkers - got a snowflake!) and some towns in Florida.