You should not blame your parents. It's like blaming people for smoking in the 50's or doing coke in the 80's. Being illegal back then was seen as something harmless and a non-problem.

More on this:

The U.S immigration system was a lot more flexible in the 80's and early 90's.
It was easier to come in illegally on a tourist visa, cross the border, get sponsored by your employer and legalize yourself.

You could even apply for a Social Security card back then with only some form of I.D.

A lot of the old timers didn't even bother trying to get legalized because they did not anticipate living in the USA for the rest of their lives. They expected to stay 5 years tops , make a bunch of $, then leave.

Why? Because they could always come back if things didn't work out.

That was the logic back then.

It was easy to leave and get back in , if you had to.

However, that stupid The Illegal Immigration Reform and Immigrant Responsibility Act of 1996 (IIRIRA) happened and went into law in 1997. It ruined everything. 3yr and 10 yr bars. EWI. Border crossing got more dangerous. It became impossible to get sponsored. Now, after that, word spread.

Every illegal that made it in would not go back - because it just got so tough to get in the usa.

Yeah, it sucks that our parents didn't fully think about us but they made their decisions with the best information that they had.
Let's not forget also that most of our parents aren't even high school grads...people who are uneducated generally struggle to make long-term decisions.
They have a present time orientation.
Plus, they are human and fallible.
They thought that if they held out long enough - there would be another big Amnesty like the one in 1986 and they didn't want to miss out. I remember vividly in the early 00's how there was still a big hope for an amnesty and it seemed possible back then. George Bush came very close.

Then 9/11 happened and immigration became even more tough.