It is all relative to each individual, and I can't stand when people make blanket statements like "homebreing is more expensive than buying commercial beer" because it just isn't true for everyone. If you constantly buy new equipment or don't buy anything in bulk, then maybe it cost more, but it's not a definite.
Just for grins here is my breakdown on equipment cost....
Starter equipment kit was $80, turkey fryer w/ 7 gallon pot was $50, new filled propane tank $45, DIY mash tun (I got my cooler for free from a coors light promotion, but lets say i payed $30 for it) $50... so $225 for my initial equipment. I fermented with the swamp cooler technique at first so no additional cost there.
I could of stopped there and made good beer, I did however eventually get a kegging setup 3 kegs plus lines and co2 tank that was about $280, plus two used deep freezers at a total cost of $200, 2 external thermostats 1 @ $45 and 1 @ $65, 2 additional PET carboys at $24 each, and additional accessories and chemicals at about $100.
So thats $963 so far spent, I buy hops in bulk and reuse yeast to save money, would save more if i bought grain in bulk, but then i would need a mill. A batch runs between $15 (4% American Blonde) to $28 (9% Imperial IPA), more if i need fresh yeast.
So if an average batch runs 21.50 X 24 Batches a year thats $516. I have been brewing for a year and a half roughly so thats 36 batches @ $774.
A tank of propane is $17 with 4 refills so far so an extra $68, water is almost nothing but lets say 50 cents a batch so another $18.
co2 at 5 refills at $12 each is another $60
963 + 774 + 68 + 18 + 60 = 1883 .... 1883 / 36 batches is $52.31 per batch or (52.31/8) $6.54 per six pack.
most beer I purchase in the store is $7.99-9.99 a six pack so I am doing pretty good.