Well, if they give you a funny look when you say 'bless you', they're probably ridiculous teenagers
A lot of people turn to other religions because they're dissatisfied with the ones they were raised with. They themselves may not even know what Wicca it is - it's difficult if you're studying yourself or in a group - and it varies from tradition to tradition.
I am Wiccan. It's a choice I don't often discuss but is very meaningful to me. I believe the appropriate response to anyone wishing me well is "Thank you."
Just "Witchcraft" isn't that definitive. Ultimately and most basically, Wicca is about Love for others. Real, divine spiritual love from our Real Selves, that we learn from suffering and that we learn for the sake of helping others. If you meet uncompassionate Wiccans, they're missing the point.
It is a complex and symbolic religion, and the forms and words it uses can seem strange. However, in other ways it is very comparable to common religions.
A search on the internet will get you many, many results.