Treating Labels like Envelopes

LO Writer provides three kinds of document constructs for similar structured purposes:
  o Envelopes (invoked by Insert > Envelope...);
  o Labels (invoked by File > New > Labels);
  o Business Cards (invoked by File > New > Business Cards).
For the purpose of this question, Business Cards are a special case of Labels, so I will ignore them.

I think it's accurate to characterize:
  o Labels as intended for a single entity frame (either fixed text or merged from database);
  o Envelopes as intended for an addressing function of two entity frames:
     -- "Sender" (fixed text, normally from LO default) and
     -- "Addressee" (either fixed text or merged from database).

But sometimes (often?) one wants to treat Labels as serving the same addressing function as Envelopes -- that is, with two frames: Sender (normally fixed text from LO default) and Addressee (either fixed text or merged from database).
  - For one-off labels, it's reasonable to treat the label frame as the Sender block (upper, left-justified) and insert an additional frame-anchored frame (lower, to the right edge) for Addressee, which is then filled in manually.
  - But what about multiple labels, with Addressee filled in from a database? Is there a "standard" way to do that? The "Labels" tab "Label text" box does not seem to have a good way to mix fixed text in one frame and field codes in another -- or have I missed something obvious?

John