Were the faces there to: deter theft? Incite laughter?
This Express an emotion? A reaction? Make fun of someone? Or something?
Did she want to communicate with someone? Did she want to eat them after lunch? Did she want to give them to someone? Did she put them in the lunch box of someone? Did she put them on the desk of someone? Did she throw them against someone? Against someone's car?
No to theseRelevant that the fruit were an apple and an orange?
No Just because of their shapes? Other meanings? Did she draw the faces in front of someone else?
Yes, some people eating with her Did he/she asked her to depict such faces?
No/Irr Do the smiles consist just on simple lines (i.e. something along these lines:

)
This, just generic angry faces or an accurate representation of someone (with hair/glasses/facial expression and so on)? Did she has the opportunity to meet someone just at lunch time?
NoWere the faces angry because: she was angry with someone? a pun is involved? she wanted to communicate that the fruits were not seasonal/healthy?
No to these Did she do it as part oof her job?
No, slight FA Did she have lunch at her work place?
FA somewhere else? relevant?
Yes Did she want to tell someone that she has been there?
NoRelevant the reason why she used two fruits instead of just one?
Yes Did she want that two people receive the fruits? Or maybe the face was depicted using the two fruits together? or maybe she wanted to place the two in two different places?
No to these Would it have work had she used two apples? two oranges?
Yes to both Shakespeare relevant? Literature/culture?
No to both