Juice is My New Financial Kryptonite

What is it about juice that makes it so expensive sometimes?? I've always enjoyed fresh juices and smoothies made with fruits and vegetables, and they seem to be becoming more and more popular and widely available. There are green smoothie books all over the bestseller lists, and people are always talking about how great their Vitamix blenders are. You can buy all these fancy juices on Amazon, as well as various health food shops, Whole Foods, etc. and they are sometimes $10 a bottle! This is exactly the kind of thing where I'd normally dismiss it as a crazy fad designed to part stupid people from their money... but I guess I am one of those stupid people, because I often find myself spending the $10! I can't resist!

I'm not buying these juices every day. But it's gone from being maybe once every couple of months to once a month... to once a week... to sometimes multiple times a week! And as the weather gets warmer, a nice cool refreshing juice will seem more and more attractive.
Sometimes I go to a place where they make them fresh, and as I watch them stuffing a handful of spinach, a big carrot, a couple beets, and whatever else into the blender, I try to do the mental math of what it would cost to buy those vegetables. I don't have a good mental price list for fruits and vegetables, though. Or maybe I don't have a good sense of weight! When I buy apples at the supermarket, I'm often shocked at what it works out to per apple-- I've seen the per pound price, but I never think each apple will be that heavy.
I comfort myself that this particular extravagance is at least a healthy vice-- a $10 juice is still less than the cost of a pack of cigarettes, and less than the average glass of wine in many NYC restaurants.

What's your financial kryptonite?