I'm surprised that this revelation comes as a surprise to you.
The core problem is that anybody can call themself a Christian. Anybody can say that they're following Christ's teaching, living a Christian life, etc - regardless of how closely it tracks with the things that Christ did or said.
(By "can", here, I mean can in a practical sense. I mean that these things occur. I do not mean that any of these things are approved of by any particular natural or supernatural being(s).)
By extension, anybody can hang up a shingle and call themselves a Christian church. As a result, you have thousands of Christian sects. These sects exist within a spectrum ranging from somewhat pro-semitic to rabidly anti-semitic.
Even within sects - especially the largest - you will find that adherents are scattered over a pretty broad range of that spectrum.
So, yes - there are a fair number of anti-semitic Christians. Their existence should not come as a surprise to anyone.
And that's before we consider eschatology...