You know? I've always thought that it's better when the person who buys a key and the person who uses that key are not the same.
The fuel reward is senseless when you buy keys to open boxes, but it makes more sense when you trade for them.
For example, I'm saving fuel to buy something (like a UCS 50%). To get 1,600 fuel I would need to play for a few months (no DMU), but if I have a lot of low-grade unis, or other stuff that I can trade, and I sell them for keys and use those keys to open boxes, every fuel reward would be a gain (except for the trade cost, of course).
For me, it's a way to turn unwanted unis and stuff into fuel or clothing; not as effective as I wish it was, but something something work hard for your stuff.
In exchange, keys give people with bad luck a way to get unis, thus balancing the game .
TL,DR: Don't buy keys. trade for them.
That would be something if a player could not trade for a UCS @ 50%, or any shop item for that matter. Any boxed open that didn't break even @ 150 fuel, would be a loss. Any key has more value in trade, then is does for its purpose of opening a box. It would take you way longer, with more of a waste in uni trades, and using those keys, to get that book, following your method.
That's assuming your gonna get a break even in fuel using those keys. That USC book, fair trade 11 keys, and they are traded at that price as well, its what i charge.
Trading for keys, and using your own fuel to buy keys, is more cost effective, and less time consuming. With no risk for loss. Is there a chance you might might hit the big fuel payouts, yeah sure, there's also a chance i'll fart rainbows after eating Skittels. lol But the probability is very low.
Not to mention "Don't buy keys. trade for them.", The whole key economy is based off players burning fuel to get keys from the store. Every key you have was bought from the store. With exception to bounty box's popping out a key now and then, which is rare.