I think "jvm is a hog" misattribution is actually part of the cause of "jvm being a hog". It implies that you don't need to worry about your memory management and efficiency in Java, because any hoggyness is the jvm's fault. With GC, you can just get away with having memory leaks everywhere and allocate millions of objects per second without any catastropic consequences. JVM software written with knowledge of memory management and that allocation isn't free can perform just as well as any other platform. As Bryan Cantrill loves to say in ever single talk: "gc is not your problem, allocation is your problem, GC just defers the cost".
My experience with those one-liner installs is that they usually work... strictly speaking. They don't scale, they don't deal with edge cases, they know nothing of your environment. They install one piece of software (in an "interesting" way that won't upgrade), and that's it.