He didn't just go to Africa for a conference, but also to supervise and help with a project (I think a school project). I'm not saying he is devoting his life to charity, but he sure seems to care more than the average 20 year old guy (and certainly much more than his siblings, apparently)...
ETA: I found this on the Amade site (we might take it with a grain of salt as it is his mother's organization speking, but I doubt it is all fake)
Andrea Casiraghi’s trip to Africa
Mr. Andrea Casiraghi, son of H.R.H. the Princess of Hanover, took part, in February and in
March 2004, in a humanitarian programme in a volunteer scheme for AMADE. Along with
M.Francis Kasasa, General Secretary of AMADE, Mr. Casiraghi had the opportunity to visit
AMADE satellites in Senegal, in Togo and Niger. As he arrived in Senegal, he could find out
how it was managed and how new programmes were implemented. Mr. Casiraghi, by suggesting
new ways to tackle difficulties, will make this centre more efficient and also will enable it to set
its priorities right. In Lomé, the Togo based AMADE is involved in vocational training for young
tailors. On the one hand, Andrea Casiraghi contributed in teaching them the basics of reading and
writing, as things stood he decided to employ a new teacher for this purpose. The whole
programme handles a wide range of subjects aimed at raising social awareness such as
healthcare issues, environmental principles, equal opportunities endeavours. On the other hand,
he personally bought a blackboard, 3 footballs, 11 school books. He also donated money to
create a football team in which both street-children of the area and students of the centre would
play together. By that time, Mr. Casiraghi realized that Lomé was a gateway for child trafficking.
As a consequence, he raised Mr. Saparapa’s awareness to this problems, Mr. Saparapa is in
charge with the AMADE in Togo. Andrea Casiraghi would like this centre to fight against this
social scourge along with other organizations. And it could ideally be part of the national
commission in charge with the child trafficking in an advisory capacity.
The last visit took place in Nigeria, Mr. Mainassara, President of this AMADE, guided Mr.
Casiraghi throughout several programmes being carried out. Francis Kasasa and Andrea
Casiraghi went to Foulan Kaoura to talk to Locals and to analize their real needs.
It was obvious to both visitors that the top priority issue was to provide the centre with
computers, access to the internet, more appropriate facilities for the area. They also decided to
start a programme focused on providing school books and a teacher to educate them, and a first
medical aid facilities. In conclusion, Andrea Casiraghi’s visit to these several AMADEs
highlighted their strenghts and weaknesses, and he put forward new means to achieve good
results in these humanitarian programmes.
(the original text was in French; this is the translation provided on the Amade site itself, but it is not very accurate...it gives a good idea of what Andrea did anyway.)