Great post! I'm an MSc Tech Entrepreneurship student with a software background and would either join an existing startup or launch my own. I'm actually attending the silicon milkroundabout event this Sunday.
I can relate to the problem in the following ways:
(1) Culture - The UK and Europe in general does not have the same 'entrepreneurship spirit' like they do in the
US. The vast majority are looking for stability, rather than risk and rewards (both personal and financial). A
recent article published in the telegraph stated that my university (UCL), has the highest number of graduates going into self-employment, and the figure was still just 2.4%, so you can imagine the rest. http://tgr.ph/tTMHaJ
(2) Value - There not so many people from a software background in my course (around 10%), so I tried to reach out to undergraduate Computer Science students in the same department in order to organise something similar to the silicon milkroundabout, but just for students on campus, i.e. match up budding tech entrepreneurs with developers and aspiring hackers. We received less than 3% interest, which kind of reflects the newspaper figure. I don't think they see the value of joining a start-up at the early stage. http://econ.st/uOw02e
(3) Presence - In the last few months, even though the term has just started I’ve received a lot of emails about recruitment fairs on campus with banks, financial institutions, large corporate IT companies etc. These are normally oversubscribed and I'm sure a lot of these graduates will end up in those companies, as they are recruited whilst still in their final year. Perhaps finance might be a factor as well. A lot of people can’t afford to work for ‘shares and equity’ after graduating with thousands of pounds in student debts, they would rather clear or reduce those as quickly as possible.
So, I would say, if you want to get more students taking part rather than established developers, you would need to come to campus and organise events there. Maybe do a tour around UK universities. Someone I met at a recent techmeetups event is actually founding a startup that teaches kids in school how to write python code. If they start early they are more likely to do it out of interest, rather than to get a secure job with a bank.