In the everlasting debate between creationism and biological evolution labels are applied to both sides by both sides, and they are usually designed to be slightly dismissive or, very often, misleading. The label that particularly gets to me is 'Darwinist' (or "Darwinism"), because it suggests that the debate is not over ideas (creationism vs evolution) but is rather over personalities, or the origins of ideas, or even gods. I believe that it is in fact partly for this reason that the label is applied. By suggesting that proponents of evolution are worshipping at the alter of Darwin, supporters of various versions of directed creation seek to elevate their ideas to a scientifically equal standing, or equate evolutionary theory with religion.
The effect is also to suggest that that the entire field of evolutionary research was conceptualised, worked on and perfected in the process of writing one book 150 years ago. It leads one to believe that nothing has changed in the following century and a half, and that pointing out errors in Darwin's original work invalidates the entire field. Evolution (as in change in populations over time) was known before Darwin, but nobody had come up with a workable method until he outlined natural selection as the causative agent. Since then much has been realised and worked into the field. Given that he knew nothing of the chemistry of inheritance, and consequently could not know of exceptions to this (such as epigenetics), it is obvious that the study of evolution has brought new knowledge with new ideas and research.
We don't call people who study (or are interested in) quantum mechanics and the uncertainty principle Heisenbergists, we don't refer to the researchers of special relativity as Einsteinists, and we don't call those pesky medics Pasteurists. These disciplines do not challenge closely held and unchangeable world-views in the way that natural selection does, and people feel less threatened by them. They therefore are less inclined to create terms of reference to frame them as something that they are not.
It is worth noting that, while choosing the term "Darwinist" to misdirect the argument, they are also steadfast in not naming themselves. They are always creationists, never publicly stating their favoured (in their minds, the only) creation story. I have never heard or read of the "Biblests", the "Qur'anists" or the "Vedaists". One would think that if labels were to be applied equally and honestly then these would crop up all over the place. That they don't speaks volumes.
I am not a Darwinist because I do not worship him or his work. He set the framework for an exciting new discipline that has survived, and indeed thrived, because it explains and interprets the biological world so well. To suggest that that is all down to the singular work of one man is to disregard the brilliant work that has been done in the decades since The Origin of Species. Of course, this is probably much of the goal – by ignoring the work of countless researchers since, modifying and improving on Darwin's original thesis, detractors can make out that this is an idea held inviolable and untouchable, and is hence a religion and should share its space in the classroom with whatever version of creationism the detractors choose. The label must be vociferously challenged and denied, because it is misdirecting people who are seeking answers in various places – places where the bastions of bronze-age belief would rather they didn't look.