Hello Leslie. To be really honest it is impossible to say, but I can say based on my 10 year on/off expereince with girls from anastasiadate that many are mostly there to get exposed and notised since they can get model jobs this way. Some also get paid under the table to be on the website but this is very hard to prove since it happen in the local agencys, while anastasiadate so to speak primary are the front page who "buy" the girls profiles and share the profit pr. letter /chat ect. with the local agency.
But in general in ukraine there are many more girls than there are men, so yes they do hope to meet someone, but keep in mind people rarely fall in love with the person they want it mostly just happen. A relationship and marriage is a long process for serious people, and there is a high risk people never get that far due to the distance ect. Anyway that was a side step. Another thing that many ukraine people in general want is a job since many are unemployed and especially jobs outside of ukraine is good, since they pay allot more than ukraine salerys... A new doctor in ukraine earn less than 200usd pr month... So the girls are motivated to earn extra in any way possible. You will often see that when a girl finish her eudcation and find a job then she instant leave the dating agency.
Be aware that a ukraine high education is not = a high education in the us. for example a doctor cant just work as a doctor but properbly have to talk half of the education again and pass some tests.. THis will be extremly difficult.
About green card, well I dont really know how many who just "use" men to get a greencard. It is no easy task moving to a new country and share life with someone, so to be honest I do not think it is that many.
However what I belive people should care more about is if the girl will leave the man once she can stay in the country and get a divorse and marry maybe a younger guy ect.. Well a kind of a way to get a new life by selling her self... Actual many ukraine girls, and also many on anastasiadate actual work as escort girls so "using" a man to get a new life is properbly better than working as an escort, and often you can find them in fancy clubs hoping to pickup some rich guy who want to pay for a night.
Many models in ukraine work as escort girls, it is big business that pay much more than a real job.
Always notise on a girls photos how she dress and if she have the latest mobile phone, think about how she maybe can afford such a telephone if she is a "poor" student. Not all girls have rich parents and often they travel from smaller citys to kiev ect. to study and live together with a room mate to afford a place to stay.
Well my answer was not 100% of what you ask, but I hope you get a little idea. Sincerely Peder.