When you request to meet someone, especially if it's a prospective client, be sure to confidently pay for lunch. Harken back to my experience yesterday, a marketing company requested to meet with us a Noon. Prime time to offer lunch.
Aside from neglecting to bring or pay for a lunch, the meeting lasted almost two hours. Now, if their presentation was knock-your-socks-off amazing, it might be excusable. But it was not.
No, you're never required to buy or pay for anything when you meet someone. But if the end of your pitch includes an ask for thousands of dollars, you should have offered to buy a $15 lunch. If you're a freelancer and can't afford to pay for someone's lunch, request a morning meeting and offer coffee. It will go a long way.