Fair question. I live in Japan. Frozen deliveries work reliably, and I don't think we'd have frozen croissants at the supermarket.

I order from a store that seems to mostly serve cafes based on their order sizes (their other products are things like a 13kg box of butter).

Where I live, if you order frozen food online, they're delivered by a courier specialized in delivering frozen goods (like UPS but only accepts frozen parcels and delivering them using refrigerated trucks).