That seems odd to me. I basically never close my IDE. Sure, I might put the laptop to sleep in between or disconnect from the remote desktop server, but I rarely need the 500 MB that my IDE consumes, so there's little point in every closing it.
I mostly program in languages like Ruby & Perl using Vim. Even with my decked out version that has 35 plugins, and some other bells and whistles, I'm on average using 20 MB of RAM. Open/Close is near instantaneous.