I plan to use another person's trash can.
Why do you not just use your own?
I do not want it to fill up before trash day.
You should ask if you can use the trash first. It can get frustrating when people fill up your trash when you still have trash to throw away.
I used the other trashcan without asking and they didn't say anything.
Not everyone will feel the same way if they find someone else using their trashcan. Your best bet is to simply ask before using the trash to begin with.