I changed my chainring on my street fixie the other day, and as I was tightening the chainring bolts up, I split a couple of the female binder thingos at the back of the chainring. I closely inspected the bolts and binders only to find them made of shoddy aluminium. 
Admittedly, the cranks themselves aren’t of the highest quality (Sunny Krown, CKT), but I expected better. After riding my damaged bike over to Abbotsford, they were able to help me out with 5 steel male and female bolts for $8.00. That’s good pricing.
I bet if I went to BSC they’d be like “er, that’s a special order item, $30.00” 
It brought back painful memories of the alloy crank bolt that split on my Truvativ cranks.
My question is why do manufacturers keep using Aluminium bolts- they’re shit!
Steel is so much better, even if it does weigh a bit more.