That's over twenty million bytes. I expected more like 5MB, 10 at the most. For a modern machine it isn't a big deal, but it's definitely bloated for what the program does, no sarcasm.
Also, most systems most definitely do not have 4GB or more. Even with 2GB though 20MB isn't a big hit. It doesn't change that it's more RAM usage than I'd expect from a program like that though.
Edit:
And I was wrong it was 30MB.
My mistake.. the vast majority (of Steam users) do have 3GB or more, though, but that's still not 4GB (http://store.steampowered.com/hwsurvey/.) As for what it does, it all depends on what you use it for. If you have all windows closed and the program itself running idle, 30MB may be a bit much, but considering I have a browser, a friendslist with around 30 different avatars, a UI and two chats with messages spanning a little over a day, 110MB isn't much. In comparison, there are two separate Skype (Skype.exe and SkypePM.exe) processes running at once, both idle and windows closed, which take up 55MB.