Singapore and HK has quite highly developed mile chasers market, which extends to the geric population. Inside Singapore/HK people in general do not carry 100s of thousands $ with them (however I have to mention here that I witnessed three times how 70+ old gentlemen or auntie walked into bank and produced from briefcase/handbag stacks of $1000 bills wrapped into newspaper). It is when you leave Singapore/HK and go to less developed places you need to carry cash.

Secondly, while credit cards/ATMs do offer convenience, consumer protection when there is a fraud is quite limited comparing to US. Couple of examples:

- This happened in Singapore: a guy lost his credit card (or was stolen), here did not release for a week. These who got hands on his card took it outside of Singapore and charged $4000 on it. Bank said that because he did not notify them immediately and 'there is no proof that he did not initiate these charges' (SIC!) he is liable for charges.

- Personal example from last November: my Singapore issued local credit card was hit with >$8000 fraudulent transactions in USD and VND - somebody was purchasing facebook credits. I never used the card in Vietnam or at shady online places. I got notified when several of these charges alerted me via SMS. But not all these charges even got SMS notification - there were 16 total, while I received notification about four. I immediately called the bank - was on my way home to office - and asked to block the card and revert charges. Yet, to have all these charges removed I had to file a police report and present that police report to the bank.

Note that bank's systems did not detect, question or block suspicious transaction like it would happen with Chase or other banks in US. Maximum I got - I was notified about these charges. And why would I who never within last 5 years of using this card used it in Vietnam, or buy anything of FB, would decide suddenly to run 16 charges with >$8000, seems bank's IT's fraud detection department did not even bother to ask...

Certain countries/places in the region are very high risk for credit/ATM related fraud - for example there is a warning here locally to limit usage of plastic for the whole Vietnam and don't use it at Kuta, Bali - on TripAdvisor forms it is regularly reported how cards are skimmed and accounts emptied.

So you get an idea - cultural traditions combined with lack of consumer protection is what makes people carry thousands of $ with them. BTW, if you observe at an US airport boarding of flights to Asia, you will notice that number of passengers are stopped by Border Agents before boarding and asked how much cash do they carry with them to find out undeclared sums.