Is there any way to change the default keys 1-8 that GB uses? Call me paranoid, but I know that keybinds are stored server-side and this could be an easy way for Blizz to flag accounts.
HB does not use keybindings. Infact, you don't even need spells on your tool bar for HB to use them.
I know, but this is a question about Gatherbuddy!
LOL, so it isMay bad.
In that case, the answer is no. You can't change the keys.
if your worried, you can always toss everything into macros, and then turn off macro syncing between WoW, and the Servers. that would prevent any kind of server side action bar scan.