That’s what the Southwest flight attendant said as he offered me bags of peanuts. People will naturally police themselves, only taking 1 or 2 bags (I took two), but the offer to “take as much as you like” pays dividends in customer experience.
P.S. This is written from a Southwest plane - yes, this plane has WiFi (Skype & the like thankfully blocked).
No amount of traditional advertising can beat this.