Role membership and DROP

I realized only today that if role A is a member of role B,
A can ALTER and DROP objects owned by B.

I don't have a problem with that, but the documentation seems to
suggest otherwise.  For example, for DROP TABLE:

   Only the table owner, the schema owner, and superuser can drop a table.

Should I compose a doc patch, or is that too much of a corner case
to mention?  I wanted to ask before I do the repetetive work.

Yours,
Laurenz Albe