This is not a large bill for a bricks and mortar store, yet moments like these are extremely common. Most small businesses do no planning whatsoever, even when it's something as simple as having enough change.
It's at the heart of sabai sabai, or relaxed, culture.
People come to Thailand for the relaxed attitude to life, where people don't take anything seriously, and always think about having fun, or sanuk.
Except that if you live here long enough, your rosy glasses lose their tint.
While I still love the relaxed attitude in general, it's ugly side means that nothing gets done theway it's supposed to, no one takes responsibility, and you can't get mad about it.
The land of smiles is not the land of service, and I've baffled several otherwise smart business owners with the questions "What is your target market? Who are your customers?". They look at me like I've spoken to them in algebraic code.
Living here has given me a great opportunity to develop patience, but sometimes not being sabai sabai would make life a whole lot easier.