I'm a volunteer.
Depending on how you look at it, I will be forced to cycle long miles, regardless of the weather, with no suitable clothing provided, often travelling late at night/early in the morning, for no pay or recognition.
Alternatively, I will be given the opportunity to spend my summer afternoons and evenings doing a hobby I love, with my own kit, in the company of some good friends, having fun and investigating a few nearby pubs too.
I'm really looking forwards to this, and am doing it entirely of my own free will. I know there is no reward other than the joy of doing it. I know the travelcard won't cover all my expenses (I live outside zone six). I know that I'm going to have a tough few rides home in the cold and wet, and it's up to me to remember to take warm clothing. I know (because I've been told) that I may have to stand outside in the open for many hours, and there may be bad weather. I know I must attend up to twelve compulsory (unpaid) rehearsals prior to the main (unpaid) event. I'm happy with all of this, but I'm equally aware that my experience could be spun into a ghastly torment by cruel organisers, if people were so inclined.
(I'm leaving the whole "compulsory workfare" argument out of this, because I've heard a number of contradictory versions, and that's more suited to P&OBI).