I don't think there's anything like an all-day muzzle. If the problem is you forgetting to lock the gate, maybe two things are in order - either bag up and remove all trash before you leave for work each day, post yourself a note by the door to check all gates are locked before you lave, and another on your pillow so you do so at night, too. Make it a routine ...

Digi is big enough to drag around a cinder block, no problem, and both the cinderblock and the chain would scratch the heck out of your floor, so neither sounds like an option that would work, frankly!