The late ikeypikey wrote on the previous page:
I've seen plenty of mattress tags - and shared many a dumb joke about going to jail for tearing the tag off of a mattress - but I've never seen one with a stamp!
It should be noted, these tags/stamps were not limited to mattresses, but also applied to many upholstered/stuffed items. Here is a small portion of Indiana's 1949 statute which runs 9 pages:
Similarly, I have 4 matching NY-stamped tags c1950 which were attached to a set of metal folding chairs with cushioned seats.
As noted before, these are listed in the State Revenue Society's catalog. Here are tags with multiple stamps:
Indiana (red) and North Carolina:
Indiana (blue), Pennsylvania and the City of Detroit:
Indiana's 3/4-cent and 1-1/2 cent stamps coming from two broad categories. Again from their 1949 law:
I have no details on rates/uses in other states, but thought I would weave some additional fabric about the complexity beyond mattresses.