Hedonic adaptation
Weak nerves and unfit risk allocation, causing poor/terrible/holy shit stop decisions at the very worst times
Divorce(all of it, the legal costs and splitting up assets, custody battles and alimony)
Fund fees, hedge funds, IPO's and hot stocks, short term ownership and churning of stocks, taxes generated thusly
Home ownership and lack of review of the costs(traditional middle class view of it), interest rates and effects, and actual fit to ones needs, as well as real estate transaction costs
(See also Second Mortgages and living beyond ones means for the consumerists)
Vehicle ownership, new vehicles, luxury vehicles, changing out vehicles often
Yes, lattes, fast food, restaurants(which are caused by hedonic adaptation or never having paid attention to the annual added costs of every unminded transaction. As a luxury rare treat in small doses, it's negligible. A daily average $10 cost is a 3650 annual cost, which over 20 years comes out to somewhere around 150k in lost wealth, and would require the stash equivalent of 91k in additional savings to cover.