I was looking through the proposed price chart for Regional Rate Boxes, and it says there will be a 75c fee if deposited at Retail. What does that mean? 

I use regional rate boxes for my business now. I pay for the postage online through Click n Ship and drop them off at the post office.

I live in the middle of a State Park, so I wouldn't feel comfortable leaving the boxes outside for any park visitor to steal, and the park office does not keep regular hours, so I can't count on the mail carrier being able to go in there to pick something up. They're too big to stick in a blue box. POs with APCs have those boxes you can stick packages in, but that's still a retail location, and half the time it fills up and you have to dump it on the counter anyway. I used to live somewhere with no street delivery therefore no pickup at your house, so I don't even know how someone in that situation would mail anything without depositing it at a retail location?

I am hoping one of our lovely postal employees can give me an educated answer :) 

The 75c fee applies if you bring them to the post office to have postage applied (retail), not if you print the postage online.

Originally, they weren't supposed to be accepted at retail at all, but must be people kept bringing them in, because subsequently they added the 75c fee.

Oh ok, thanks! I was so confused, because I didn't think the clerks were allowed to sell you regional rate postage at the counter at all.