A lot of people use the Promo category for items that were issued as part of a promotion, free with purchase, proof-of-purchase mail ins, point of sale, etc. However, the category definition FAQ defines a Promo set as cards that were issued to promote a trading card product:
FAQ: How should sets be categorized?
Promo
Cards, usually given away at events, to promote other releases. The card themselves usually contain "promo" logos or labeling.
By that measure, the types of sets you describe above seem to fit better in the Oddball category. Personally, I think the "Food Issue" category should be expanded to include cards included with other types of products (after all, the nature of the card set is no different if it was sold with corn flakes or motor oil, is it?), but that's not the way the rules and guidelines are currently written.
-Tom
Ted Musgrave card collection 98.9% Complete: Cards Known: 1013, Cards Owned: 1002
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