Not sure what you mean 'the launcher won't work' without EADM. I do not have EADM and am able to use the launcher to install sims3packs, I don't use it for anything else. Mind you, I clean out my registry before re-installing the game anyway.
Do you use a MAC? if so they don't have the EADM. Every time I have had a problem with the EADM, usually when it tries to patch and the patch fails, the launcher ceases to function until the EADM is fixed. Everytime I start the launcher, it also starts the EADM, whether it is being used or not. Like you, I usually only use the launcher for sims3packs, or to run a check if there is a new patch or not, but don't patch that way.
My experience has always been a broken EADM equals a broken launcher.