Did the same to me when I purchased a hybrid bike last year which unfortunately doesn't fit in the back (misses by literally 2 inches). Other than shoving something into the latch like you mentioned, you can't just hit a button to turn it off (at least that I am aware of).
Thanks phoenixgreg, I'll have to try that after work. I'm sure this will work as I don't haul long loads too often but you'd think there would be setting similar to the backup and seat belt warning beeps that can be modified.
Toyota doesn't want to pay $25 million when a kid falls out the back because someone forgot they had turned off the alarm.
http://priuschat.com/forums/gen-iii-2010-prius-audio-electronics/94732-hatchback-open-warning-beep.html#post1338255
Understood...but like I said, I few warning beeps during the vehicle start up process along with a constantly blinking door open indicator on the dash is perfectly fine with me. If you drove 45 mins with that beeper going...trust me you'd be wondering the same thing.
Thanks, I'll definitely do that next time I have to load the bike into the back. 30 minutes driving with it going off was too much...