Now what do you give me in return?
What can I do with a bitcoin once you have transferred it to me?
I think the idea is you can then exchange the bitcoin for goods/services/fiat currency etc, the same way you would exchange a $100 bill for other stuff.
I don't need to be able to
do anything intrinsically with the bitcoin or the $100 bill (i.e. I can't eat or drink either of them) for them to have exchange value.
Gold always was wanted because it looks great. People like to wear it and touch it. When I exchanged something for gold I received value.
The Dollar only had value because government forces us to accept it. If I exchange something for dollars, I get government guns to make sure it will buy me goods
Now what about Bitcoin? Why Exchange Something for Nothing? If your answer is because you can transfer Nothing cheaply let me tell you this:
Incurring a cost (something) for transferring nothing is a waste not a benefit.