It is actually a legal requirement to be able to produce ID in order to use food stamps (and, I presume, the food stamp card these days). I once prevented food stamp fraud simply by asking for photo ID from a couple of guys who presented a food stamp card with a woman's name on it.
This idea that there are multitudes of citizens who do not have ID is completely bogus. It is also a blatant and transparent measure to enable vote fraud.
One has to wonder why the exception is allowed if the ID laws are really so discriminatory. The only security is matching signatures which deteriorate over time. If someone waltzed in and claims they are xyz, produces a reasonably good signature match, then the law says we must let them vote. It doesn't tell us what to do when the next xyz shows up to vote.