The reality of the situation was, they weren't running out of meat literally. They were running out of meat on the food line, where it is kept in a massive double-boiler. The meat he spoke of was in a metal pan that holds about eight to ten pounds of ground beef.
If he did genuinely use it up, he would have to start telling customers that they must wait a half hour for one taco, because they have to warm up more meat. That was the being fired he was referring to. This is not the customer's fault. It's either the crew's stupid fault for not dropping meat in the rethermalizer on time, or it's the manager's stupid fault for telling the crew not to drop any meat, because he wants to minimize the amount of carryover food for the next day. Any food that Taco Bell doesn't use up, and that will keep in the fridge, and that isn't dirt cheap, will be committed to carryover at the end of the day, so that they can mix it with the new food in the morning.
The fault of the crew is something that happens very frequently at my store. It is a part of the disorganization that gives Taco Bell a reputation for being the slowest fast food chain in existence. For fries, the rule is that when the fry holder starts getting low, the person doing fries should drop some fresh fries into the deep fryer. They cook for two minutes and 15 seconds, more than fast enough to keep the flow going. Every day I am there, it happens at least once that someone has not paid attention, and the fry holder runs out of fries. This should never happen. It causes customers to twiddle their thumbs and give us the evil eye while we twiddle our thumbs and give the fryer the evil eye so it will cook faster. It doesn't seem to matter what manager is present, either. It always happens.
For the curious, the rethermalizer is a tank full of water at 195 degrees Fahrenheit. We drop packets of cold food into it and take them out when they're warm.