Because when you make the places to get them few in number and difficult to get to, then make the lines to get them very long, you create hurdles for people who have jobs that are not overly friendly towards long or variable absences.
This is intentional, much as many places in the United States have reorganized voting locations to themselves be difficult to get to. Disenfranchisement is intentional.
> Don't you need to get a driving license to drive? ... Do disadvantaged groups not get driving licenses?
Many in the United States live in urban areas where they're not required and where they may not be economically feasible. (These folks tend not to vote for the people who are pushing ID requirements.)
> A passport to re-enter the country?
The set of Americans who never have cause to leave the country is very large.
Why is obtaining an ID "intentionally designed" this way. Don't you need to get a driving license to drive? A passport to re-enter the country? Do disadvantaged groups not get driving licenses?