Over here in East Asia (Taiwan to be exact), people usually carry a myriad of cards due to the various perks each bank provides. For example, I may get a Visa card with cash back for shopping at Carrefore/Costco/Supermarket, Another Mastercard that provide free roadside assistance and airport limousine and airport lounge benefits, and a JCB card that provide me with buy one get one free movie tickets and 20% discount at certain restaurant chains. People usually have 10-15 cards easy.

Myself when going abroad will decide which card to bring by looking at the destination.
If my destination is Japan, I would definitely bring a JCB branded card with it free lounge access at all major Japanese airports, as well as being the most accepted card locally.

Some cards also offer a higher % cash back when being used abroad, so I will make sure to bring that card as well.

My regular repertoire of cards when traveling usually consist of 1 Visa, 1 Mastercard, 1 Amex (US/Europe/Middle East), 1 JCB(East Asia). I used to have Diners Club but am finding it virtually useless in a lot of locations outside North America. All of them being high cash back/airline mileage cards.