For example in United States it is customary for people to smile often, especially those working in customer service.
In Ukraine, smiles are only seen when something funny or entertaining is observed.
If you're not feeling it, be clear but kind: "It's been great meeting you, but I'm not feeling it on a romantic level." It's hard, but it works. If invited into a family home, it is traditional to bring a gift. These cultural differences add a certain amount of charm to these beautiful ladies.