I personally can't see it as being profitable for an individual for the following reasons;
1) It is most likely a very low margin business. (I may be wrong) If I am correct in the ASSumption
then you would have to do a LOT of volume to be profitable.
2) You would have to find a location with a very high volume of traffic. The most obvious would be a mall. You would have to cover kiosk rental and staff the location the entire day.
3) You will be competing with a lot of the "Big Box" retailers who have gift card displays in their stores. I have seen them set up in Lowes, Wal-Mart, Walgreens and numerous other stores. You have to answer the question "why would people buy from me when they can just add the gift card while checking out at the big box store".
4) The link provided by Ron mentions that you could manufacture/supply gift cards to smaller businesses. Most merchant card services companies have an optional "gift card service" available to customers already in place. It would be hard to compete with these services.
5) It is a highly seasonal business. I do not think you would see the volume you need to be profitable at any other time than during the Christmas season.
It comes down to what your break even point is. I would certainly complete a very thorough business plan before pursuing this.
Disclaimer- I don't know what I am talking about. This is a matter of opinion pulled out of thin air and dangerous assumptions. The value of this opinion is worth exactly what you paid for it. Mileage may vary. Taking this advice may result in stomach craps, intestinal bleeding, and heart failure. If your condition worsens while taking this advice please consult with someone who knows what they are talking about