The overwhelming voter ID arguments I've heard is that those laws disproportionately impact poor people. ID is an excess cost and requires the ability to take off work in the middle of a week day and travel to a designated location. Which is difficult for people working multiple minimum wage jobs and people without reliable transportation. The racial aspect is that these holdbacks disproportionally impact the black community so much so it can almost be used as a proxy for "black" in some areas.

I have never once heard anyone say the reason is that they won't know where to get an ID.