Finding one that fits
There is not a lock on the market hat fits the lifetime cooler tightly. A wild series of hardware is required to make it work. The average lock leaves too much play in the lid to keep food secure. The IGBC requires the lock to allow less than 1/4" of play in the lid.
Keeps your buddies out
You and your buddies are out camping in the middle of nowhere, there is only one key to the cooler and therefore no one locks it because it’s inconvenient. Let’s face it, out in the back country no one is out to steal your food. They may want the whole cooler but that’s a different situation.
Inconvenient and takes too long
Which leads to non-use.
No one want to dig out the keys and fiddle around with locks for a minute just to get another cold one from the cooler. Because of this the locks stay on the ground and do nothing to protect Bears from accessing your stash