I couldn't find the source of this. Image search failed me.
Previously, previously, previously.
Hm, image search plus "coin heads" as a search term finds this imgur upload as the source, looks pretty recent, and none of the comments are calling out OP for reposting. All the Reddit posts are after it.
I imagine it would be hard to make coin operated machines work properly with head coins, also, what should be on the reverse? If they are going to be heads only, why make them be flat, make them little disembodied heads.
The ridges on the edges of dimes and quarters, along with their size, are how blind people tell coins apart.
Yes, it is obvious that a blind person would not be able to discern the differences in the size and shapes of these heads. After all, they have never seen a human head, so any difference would be opaque to them.
Also: cut out penny Abe Lincoln looks like Tom Hanks.
Run, Lincoln, run!
Somewhat related, a guy I know cuts out hobo nickels and mounts them on jewelry.