Why does Mexico want the US to open it's borders and relax it's immigration laws without being willing to reciprocate?

I’m from Arizona and there’s been a lot of back-lash from all over lately about Arizona’s efforts to curb illegal immigration within it’s borders. The comments I’ve been reading at the end of all the news articles seem to indicate that people who are against Arizona’s efforts want an unrestricted access by all people to all of the US at any time, for any reason. The majority of people in favor of Arizona’s law seem to want zero access, zero tolerance. I’m not totally against the idea of an open border with certain stipulations. However, Mexico has some of the most draconian immigration laws in the western hemisphere, if not the entire world. Shouldn’t they open their borders and relax their immigration laws at the same time as the US?