For me, AG turns out to be more expensive than K&K, but that is primarily because we brew with quality ingredients of grains, hops, and yeasts. The advantage is that you have much more control over exactly what you want to brew.
There are ways of containing the costs, eg culturing liquid yeasts into multiple starters, buying grain in bulk etc.
In the end, we brew AG because we enjoy the process and the control it gives us, and generally, but not necessarily, produce better quality beers.
There is a cost involved in setting up the equipment, and an ongoing cost in time, so it comes down to what your own objectives are.
So long as you enjoy what you do, and are happy with your product, then that's all that matters. Cost is in my view a secondary consideration, as the beer produced by any of these methods will always be cheaper than commercially purchased beer.