@latichever: Yep, people want to justify to themselves.
However, as @BobWallace has noted, a lot of the perceived difference is due to marketing. In the estimation of @starbright (who is and has been faculty at a Canadian public as well American publics and Ivies), while there are differences between publics and privates, they tend to be overstated by parents and kids not familiar with higher ed.
My take is that if you compare top public research U’s with elite private research U’s, the in-class education can be very similar (for a kid who wants to make it so). Certainly, the quality of the faculty will be almost the same. Privates may have more money to spend and there will likely be differences outside the classroom. However, in terms of tangible advantages being the same/better/worse, that really depends on the kid, goals, and school & program.