I guess somebody has different priority, but free lunch in the lounge isn't for most, you can only eat so much köfte and tavuk before you want something else.

For such layover with limited time, rather than spending additional hours in the lounge, try to explore the town (not tourist trap like Sultanahmet but other spots where local residents live, eat, and commute) and get some cheap lunch elsewhere, you don't know what you're missing. Take the subway and get off at Ataköy Şirinevler, this is only 2-3 stops from the airport, there are local cafes (lokanta) and street food stands open until almost midnight.