Just to clarify what was said before about AGM batteries, when an AGM battery vents, it's because something is wrong. Either it was charged too fast or discharged too fast or it is in a condition called thermal runaway, which occurs when a battery is overheated. In an ordinary scenario, it is just fine. I would place it in a cabinet in most cases. In some instances though, it would make sense to have a separate container vented to the outside. It all depends on your appetite for risk, and how you are using and controlling the battery.
Cell carriers will place them in the same cabinet as some very expensive electronics, When there is need for a lot of them (AGM batteries), and a separate cabinet makes sense.
