I've also had this issue, it doesn't happen 100% of the time.
Example: I asked my sim to grill hot dogs, he was in the house and i cancelled. but he was still walking to the grill and the interaction finally cancelled when he got to the grill outside.
Posting to let other affected players know they're not alone. This happens in my game often enough (& in enough households/neighborhoods/worlds) for me to consider it part of how things are in TS4, but all the same it doesn't happen nonstop. I'm not familiar with making videos, but will try to remember to attempt one the next time an action won't cancel, or when the game wipes out the cancelled action (the X across the now-faded action icon disappears, and the icon refreshes itself--is no longer faded).
