They’re actually not prepaid, they’re counted as postage due at the destination office and either charged to their account automatically or paid at the time of pickup.
There are lower cost options like nonprofit or third class postage, but that’s usually what they’re paying to send out the junk with these business reply envelopes in the first place. Business reply mail AFAIK is charged at the first class postage rates.
There is no way that those prepaid postage meant for a letter is gonna be good for 70lb.
The postal service has to have lower cost options
They’re actually not prepaid, they’re counted as postage due at the destination office and either charged to their account automatically or paid at the time of pickup.
There are lower cost options like nonprofit or third class postage, but that’s usually what they’re paying to send out the junk with these business reply envelopes in the first place. Business reply mail AFAIK is charged at the first class postage rates.
I know it’s not technically prepaid.
But it’s wild that the postal service wouldn’t have an option here to only accept letters.