Digital BW, The Print

My frustration with all these pre-cut mats is that I don't want to
lose half an inch in both dimensions of my print. I prefer to show
some of the paper of the photo in the window (say 1/4" all round). So
that means I can buy a pre-cut mat for a 5x7 and use it on a 4x6
print, but none of the other sizes work. Am I really the only person
that wants this? Is everyone else happy to crop the print when they
frame it?

Daniel