Andreas,
It is best first to understand about the origin of the dreamcatcher.
Dreamcatchers are a tradition from the Ojibway, usually small and measuring only a few inches. Made from forming a small tree branch / willow into a circle, and using sinew to form the web. A feather would be attached to the web. This would be hung near to where a child slept to help prevent nightmares.
Today, you will find them made of much sturdier things, to last longer.
In the 60's / 70's, during the pan indian movement, they started getting popular among other tribes, although not traditional to these tribes.
Is it proper to sell dreamcatchers, yes why not, they are a craft, not a scared item.
However, you can walk down any high street, and see dreamcatchers for sale. 99.9% of these will be mass produced in Asia. This is another theft of our culture, so do not buy them. Buy genuine native crafts, then at least you know you are supporting the people they represent.
As for a practice of giving a dreamcatcher, I don't know of any. I would give one as a gift, normally to a new born or child. But now you see them hanging in cars. So a gift is a gift, and nothing else.
I hope this helps you a little
