I find the majority of expats/immigrants I meet here in Poland fall into three types:
Well, hmmm, I'm not sure here. I never owned a company in Britain, never supplied jobs etc but I worked and paid taxes... does that make a non-contributor in my own country? In Poland I am a one-man firm because the majority of employers in the ELT industry don't want to pay my ZUS etc for me. Unlike many Polish migrant-workers in UK, I am not sending my wages home, so I imagine my taxes in Poland are helping towards paying for the limitless posters for elections, and the paperwork to prevent my local roads being repaired.
Needy? Well, my Polish aint great, although I can survive OK when I need to. Likewise, the amount of people who either insist on trying to speak English to me (either they find my Polish painful or they want to practice/show off, or are just being friendly) or express gratitude for having a non-Polish speaking teacher (so they HAVE to use English) suggests there is a number of people who don't mind my linguistic disability.
True, the other half is Polish and one of the reasons for me moving here was that when we married she would have found it a lot harder to move to UK (the British embassy once told me not to tell the border officals that she was my fiance in case they thought we would marry in UK to get her residency!). I got a job which has served me well and which I've been able to develop in, whereas she would probably have ended up as a waitress, rather than the job she holds now... as director of a very successful Culture House, which is recognised nationally... and where I occasionally assist with projects etc.
I suppose my work with village schools and Special Needs groups might class as a contribution, although some of it is paid... Not sure about my theatre and music concerts, cultural activites etc
Ex-pat holes? Avoid like the plague (although I don't know if there are any where I am)