Necessary equipment to jump into AG brewing:
1) Large kettle capable of doing full 6-6.5 gallon boils.
2) Large enough propane burner setup to cook said kettle.
Both of these needs can be satisfied by using a turkey fryer setup. Most (or at least many) AG brewers started out this way. Total cost is less than $75 plus a propane tank.
3) A wort chiller capable of chilling your boiled wort down to 75 degrees quickly. Most people start with 30-50 feet of 3/8's inch flexible copper tubing and some hose clamps and vynil tubing...all from Lowe's. Total cost is less than $70.00.
4) A cooler to convert to a mash tun. I had a round 5-gallon rubbermaid and added some scrap copper and some plumbing parts...total cost, less than $30.00.
So for less than a couple hundred bucks you can begin brewing all grain batches. A typical 5-gallon batch will run you less than $20.00.
Don't believe for a moment that you need to spend thousands to start brewing from grain. And as for the difference in quality...just hang around here long enough and you'll pick up on the comparison analogies like (fresh squeezed orange juice VS concentrate, home made marinara sauce VS ragu...etc.)
Extract and PM brewing are great alternatives to buying commercial off the shelf. But all grain gets you to the real heart of what all microbreweries do.
Here's a pictoral
that is very helpful in understanding how simple AG brewing is and how little you need to spend to get into it.