Oxford has a serious begging problem. This comments to this article give you a pretty good picture.
Most beggars here are polite, and I’m polite but usually distant back. But a few can be aggressive. In fact, the other night I felt threatened to the point of coming very close to running to the (thankfully) nearby police station.
I will give money to some “buskers” (performers), however. There are a lot of those in Oxford, too. But if they are trying to earn something and are doing a good job at what they do, I respect that.
As for just straight out begging, it’s a bit problematic how to respond as individuals and as a society. I prefer to give to agencies that are better equipped to effectively address the needs of the poor instead of enabling harmful and often disruptive behaviors.
But in any case, people should not be threatened or harassed simply because they are walking about and minding their business. And Oxford does have a problem in this regard.