There are no "overlapping" events. But, you led me to the solution!
**It's the "mouse is over" conditions causing those 30k checks.
So, even with collisions disabled on all applicable objects, those mouse conditions alone give me 30k checks/sec. If I disable my "Hover" group, which contains all these "mouse is over" events, I get 0 checks.
Thanks fellas. Also, I'll assume now that there is no global disable, but I was barking up the wrong tree there anyhow.