Wow.
I wouldn't have expected 1/2 bdays to be controversial either.
I have known plenty of people without 1/2 birthdays to delays parties. People with March bdays want pool parties, so they wait. People have relatives or friends that can't make it, so they wait a month or two.
For those that are so up in arms against 1/2 birthdays, do you HAVE a child with a birthday right next to Christmas??
While my mom remembers my girls birthdays, she has come close to forgetting on several occasions that my son has a birthday as well. She is so focused on Christmas, she doesn't remember the birthday. The only reason I've seen she has, is because in the course of talking with her, I've happened to mention things like, well we finally decided on a cake. This isn't intentional prodding on my part, but simply conversation. Twice now, after conversations like that, I've realized, she had completely forgotten about it!!
I will also come out and say it. It IS about the presents. (Obviously, there is far more to it, but this does have an impact as well.)
The difference between what my son receives for his birthday, and what my daughters receive for their non-holiday birthdays, is very noticeably
different. This isn't just a small difference, but a very large difference.
On his first birthday alone, my sister completely forgot about it. My mom did forget about it, until I happened to mention it. While she made a huge deal about my other kids first birthdays, she did next to nothing for him. How many people grandparents forget a child's first birthday? :-(
While my son is only 3, it isn't a big deal, but he is going to reach an age at some point, where he isn't going to understand why both his sister's got a ton of presents from their grandparents on their birthday, and he gets next to nothing, and why what he gets is generally an afterthought.

Sure, it will open up conversation, and I will have to have a good talk with him at that point, but it is fairly sad that he is utterly forgotten.
Now, this isn't about, oooh...let's get more presents. I would be just as happy that my girls got less, but that hasn't worked. It is about at some point needing to explain things to a 4-5 year old, when he notices and doesn't understand why things are so different.
The only reason I haven't done a 1/2 birthday, is because we do not have relatives here. I suspect if we changed when we celebrated it, they would forget even more. If I did have relatives nearby, and did have birthday parties with them, I would have changed the celebration to a 1/2 birthday a long while ago.
I feel all kids need to have that special birthday day, and with it around Christmas, while as a family we make it as special as possible, our relatives do not. Even then, though, this past year we celebrated his bday 2 weeks early. We felt that was the best way to insure he wasn't feeling like his birthday was just continued Christmas activity.
As for 1/2 birthdays, his 1/2 birthday coincides with my dh's. Because of that, we do give my ds 1-2 small 1/2 bday presents on his 1/2 birthday as well.
Tammy