The reason is that is informational and doesn't effect the bottom line of a return ... thus it is not needed. File the required forms as required and you are good.
But if you are dying to send in a new Sch B then attach one to a 1040X )with no changes in column B if you like... but it is a waste of paper, ink & postage for something that will be pitched in the trash when it arrives.
<a rel="nofollow" target="_blank" href="
https://www.irs.gov/pub/irs-pdf/f1040sb.pdf">https://www.irs.gov/pub/irs-pdf/f1040sb.pdf</a>
<a rel="nofollow" target="_blank" href="
https://www.irs.gov/pub/irs-pdf/f1040x.pdf">https://www.irs.gov/pub/irs-pdf/f1040x.pdf</a>
