It is not necessary that everything the West does is according to logic. The biggest proof that it is the invention of the west are the song words without which this function is not complete viz. 'Happy birthday to you.' No one says, 'Happy birthday celebration' or 'Happy Blessed birthday' or any other words of this kind. This disease of celebrating birthdays was never prevalent among Muslims before, but since Muslims started living alongside the non-Muslims, they have been influenced by them.It isn't only a "disease," it's eee-ville:
It is stated in a Hadith the worst Walima feast is the one in which the poor and destitute are left out and the wealthy are only invited. Another object of the birthday parties is show. Islam encourages simplicity. By this attitude of show, the poor feel inferior and deprived and the rich have a superiority complex. Also, in these gatherings, music, singing, video filming and the taking of photographs and other un-Islamic and forbidden acts take place. May Allah TaÃla guide us and protect us from all these evils.Now, I really don't care whether or not Muslims celebrate birthdays and sing the song. I would merely point out that the above way of thinking makes it a lot more difficult for Muslims to get used to/fit into non-Muslim lands.