Most people only know JWs as the people who knock on doors to preach, or who are next to the stands with WT magazines and tracts. JWs tend to be pretty mild and approachable in general, so people who know a JW or two will usually tell you that they're nice people.
The other stuff --especially about birthdays and holidays-- probably seems weird to them, but since it doesn't affect them directly, it's not a big deal. At my old job, they actually offered to change the name and description of the annual Christmas luncheon and office party, because they felt bad that I would not take part. I explained that it was still, in my mind, a holiday occasion. I think they admired my willingness to take a stand, but also it did not affect them-- they were able to enjoy both, whether or not I was there.