Canadians, what kind of hoops do you to visit the US??

[Mexivoof]

We were talking to the receptionist in our Hotel . She is Mexican with a Canadian Husband (I don't know if he lives in Canada or Mexico) from British Columbia. She visits Canada regularly but also has a sister in Austin TX.
I do not know if the sister is here legally (there are some questions you do not ask!) but she will not visit her because of all the road blocks the American government has thrown up. She would have to appear at a hearing in Merida (and pay for a nights lodging) to prove that she has employment and I can't remember what all else in Mexico before she can enter the states.
As an American I have never had any hassle entering any country (except for that missing front plate on the car I was driving into Windsor).
Most if not all of the 9/11 hijackers came in over the Canadian border; WHY are we UBERharrasing employed Mexican women who just want to visit their sisters??