See the Sarfraz question related for a few opinions.
You can do this with streaming, because it’s more difficult for casual users to “steal” streaming content than uploaded content. Harder, but not difficult.
You can try to do this with DRM. DRM is a very attractive idea for content owners, but in the end you have to weigh all the pros and cons. Obviously, getting some degree of protection for your content (for you) is a pro, but also consider the very large “cons”: DRM is inconvenient for your users. This requires infrastructure support. This is not a hindrance for professional thieves or even motivated amateurs. You can quite easily find "DRM-deprived" copies of almost all of the content; as soon as one person is in trouble, they usually make it available to others (free or at a price).
At the same time, you are using (wasting?) Valuable development time, trying to prevent something that cannot be prevented in today's world.
I would say go streaming because it raises the bar, and then just accept that your content will be received without your consent by a certain percentage of users. I affirm that you can reduce this percentage by making it simple and convenient for users to receive content with your consent, which is exactly the opposite of DRM.