Dave, good points worth considering....including the
Jr. wendy option. Yes siree ...lol

Anyhow, just spoke to Applebee's this evening, and got the sweet and lowdown :

(These ON Top of the price of burger)

Onion (plain or sauteed) -- $.50
peppers ----------------- $.50
shrooms ------------------$.50
Bacon strip ---------------$.75
Pickles (xtra) -------------$.50

Focusing just on their onion -- a 50 Lb. bundle of onion is likely no more than $10 - $12. Say there are 50 onions in the bag, with 1 onion contributing to 10 burgers.
50 x 10 =500.
Roughly then, they are pocketing $250.00 for their $10 purchase of onion.