In general these will be young people who are out to enjoy life and whilst many adapt a more moderate balance lifestyle, there are always some who carry on.
Certainly with the lack of incentives for savers, this certainly does not help motivate people and why should it.
What I would be interested in is a graph of fiscal behavour done per age groups and fiscal income. Also if they are single or married or have children. Then I believe you would see a more measurable trend.
Though it is worth bearing in mind credit card companies prefer people who live like this as they make them more money than not and with that is it a testiment to how well credit card marketing is actioned I do wonder.