Why are alternative education methods so often rejected by mainstream schools and teachers???

In my summer class today, my professor was talking about the Montessori Method and kept on saying that it was bad for kids and that they don't learn the fundamentals needed to be successful in school.  However, he also kept saying that teachers need to stop forcing kids to learn how to read in Kindergarten, and let them figure it out in their own time.  Now, isn't that Montessori-ish?????

I love the Montessori Method, and while I haven't actually seen it in practice, I've researched it quite a bit.  My mom used to be a preschool teacher and is now an early elementary teacher.  At her preschool, she implemented a good deal of hands-on learning and very little worksheets.  In each of the classes, at least 5-8 of the 12-15 would go on to be in Gifted and Talented Programs.  That's a pretty amazing success rate, if you ask me. 

It all comes down to this:

Kids should not be forced to learn how to read while still in Kindergarten.

Reading is a developmental skill, and kids are mentally, physically, or emotionally ready to learn this until first grade. 

Now I understand that many Montessori kids learn to read before Kindergarten, but it is voluntary, and the kdis just sort of pick it up in the classroom.

My mom and I have seriously considered opening a Montessori in our town, because there isn't one anywhere near us.  Maybe when I graduate.  I really don't want to teach in a regular classroom.  Right now I'm considering Gifted Education or Austism Education.  Mizzou has a FREE Austism Education master's program, so I may do that if it's still FREE in three to four years.  That's another area that has always fascinated me.  Gifted, Autism, and Montessori.