Unpaid Internship - No responsibility

So this summer I have the extraordinary opportunity to work for a bank in NYC. Unfortunately, it is unpaid but with the lack of income also comes a lack of responsibility. Most of the day I spend doing errands and putting together excel sheets for my bosses. They show me round the market on Bloomberg and explain what is happening and what they are looking for. Im slowly learning the market and banking language by reading and researching on my own along with talking to my FA. What's driving me insane is the lack of ability I have to show the people around me and the bank what I can do. This mostly results from the fact that I am not getting paid, so the bank won't grant me the responsibility.

What really concerns me is; what am getting from this internship? Most will reply, "Whatever you put into it.." but there is only so much I can put into this internship. I try to do everything I can but I still don't have the same responsibility of my friends with paid internships.

SO... How do future employers view these types of internships? Is there anything I can do to to get more responsibility, and how do I make connections with the people around me so I can receive good recommendations?