The RAM footprints of most development tools on Linux are also less than on other operating systems, due to shared libraries and not just shipping every dependency bundled with binaries. A developer on OSX told me he was close to maxing out his 16gigs of RAM, blaming it on having to run 2 vagrant VMs simultaneously while working. While I wasn't able to establish a conclusive cause of his sizeable memory consumption (he was busy), I spun up 3 vagrant VMs of my own, simulated work, and opened/visited many more sites in Firefox to try to hog resources. I could hardly break 4 gigs of RAM used (out of 16), in Ubuntu 14.04. 8 gigs might not actually be so bad if you're doing development work using tools that aren't shipped as complete packages, but rather adhere to the unix philosophy.

I look at my RAM usage on ubuntu sometimes and I suspect that about 40-50% of the machine's total use is due to adblock running on firefox.

Give µBlock[1] a try, it seems to use quite a bit less memory. I've also found it to block more ads by default.

[1]: https://github.com/gorhill/uBlock

Gen. Alexander's talk at Def Con 2012 sounded pretty earnest, too...