My two sats... While that miiiiiiight work, it might also be more "risk" than the average vendor on the beach is ready for. My personal preference, I like to ask and if they say no, say "No ¿todavía?" Which basically says (without saying directly) that they should probably reconsider.

And then as a personal form of outreach, because I'm actually trying to help that person welcome Bitcoin energy into their lives, I'll offer to pass them a few mil (1000 colones or $2) in says as a tip. It's a lovely interaction.

Grown men get teary with gratitude. 🥹

And I know that the next time someone asks, they'll happily say yes.