When I was a kid (in the 90's and early 2000's, so not that long ago) restaurants were more of a special treat than a weekly occurrence, and trips to Europe or tropical resorts were for the affluent or maybe as a graduation present. Now I see people (with kids, and from the same socioeconomic background that I'm from) on annual vacations and going out to eat multiple times a week. Not to mention a greater number of vehicles per adult and more tech gadgets. Of course this isn't a representative sample, but it's interesting to note.
I do think, however, it's fair to say that the millenial generation financially differs from at least the Boomers (not sure about Gen X) in that they have different responsibilities. Real estate was much more affordable based on average income (at least in Canada,) post-secondary education was more affordable and less necessary, and childrearing was more centric. People in their 20's were more likely to buy a house (which then provided solid investment-level gains) and start a career and/or family in their 20's. You kinda had to. Now that there's much less pressure from society to get married and have babies, coupled with the high real estate prices and what I'd call societal pressure to enjoy life*, leaves lots of millenials less concerned with saving and investing and more concerned with shorter-term fun.
*In my social group from uni, saying you don't absolutely love international travel is what I believe to be the 1950's equivalent of a woman saying she has little interest in having babies.