What is wrong with immigrating legally? Hispanic groups can split hairs and play games all they want, JUST IMMIGRATE LEGALLY. 99% of all European immigrants did, what's the big deal anyway?
MaryL.... You are not new here in immigration section and I know you already knew why they don't migrate legally. But I will answer your question.
Let say if you are a Mexican or Asian trying to migrate to US legally.... Approach US embassy. These are the questions.
1. What's your purpose?
2. Why do you want migrate to US?
3. Where are you going to live in US?
4. How will you able to support yourself?
5. What is your profession?
6. Do you have a clearance from your government to leave your country?
7. Clearance that you do not criminal back grounds.
8. Language... How will you able to assimilate with only Spanish or Asian.
9. Clearance that you are healthy.
You are NOT going to get an immigration visa... You will only get a tourist if you qualify financially.
People that want to migrate to US legally through relatives sponsorships waited several years before they can come here to US. American citizen sponsoring a spouse from other country will take at least 2 years. Immigrant status will take 6 at best to 10 years.
NOW..... Your question again....Why can't they migrate to US legally? Don't forget the cost minimum at least $5,000.