Mdf doesn't warp like wood does in dry environments. It's easier to finish smooth (laquer and/or laminate). It's price is between softwoods and hardwoods. It's holes and cuts are very accurate in cnc processing. So yes, I understand the reason it's widely used in the industry.
It has certain properties that come in handy. Not that I'm a big fan of it. I had to work with it quite often when I was working in interior building and I had frequent nosebleeds back then, especially after a day of sanding and cutting mdf...

But: If you don't like it and can/want to use real wood, why the question?

so how much more per square feet is real wood compared to mdf if you where to do a house lets say in real wood as pound of doing it in mdf

Depends on the application. Base molding, for example. Similar styled base moldings are half the price in MDF. Some woods there is even more of a difference.

where can i find real wood moulding

Uhm.. Do a house in mdf?
What are you building?
And what do you want to use the mdf for?

MDF is also more flexible than real wood when using it for trim. Therefore, if being used for baseboards or crown molding it allows the installer to work with any humps in the walls, ceilings, floor, etc. It is also produced in longer pieces than wood so you have fewer joints.

You should be able to find real wood molding at most local molding companies.

MDF looks great, is easy to work with, is cost-effective, and takes paint well. If you're staining your trim, then go with real wood. Otherwise, go with MDF and spend your money on something more important.

Mdf dents very easily. It's also made with all kinds of adhesives mixed with fiberboard.