The answer to your question is: No, the expensive school is not worth the price difference. This has been studied over the years a couple of times, and I will finally get around to starting a thread to discuss the most recent study. Here is the gist of the argument: If you study how much money people are making ten years after graduation, the schools seem to fall into many different tiers of excellence. (Yes, I know that making money isn't everything, but it is a big part of the rationalization that people give for blowing a fortune at the top tier schools.) On the surface, the outcomes would seem to justify the greater expenses. But the samples are biased. A very top tier school (Ivies, a few near-Ivies) gets students who have a lot of factors that predict success (intelligence, having the ambition and confidence to apply to the Ivy tier in the first place, etc.). How do we know that any value is actually added by going to the Ivy tier in the first place? Ditto for the next tier, the third tier, the fourth tier, the fifth tier, etc. These are not random samples of students.
What if you took two students with the same SATs, who both applied to the top tier and got rejected, both applied to the second near-Ivy tier and got accepted, but one decided to go to the third tier while the other accepted his spot in the second tier. Does it make any difference which tier of school they went to? In terms of making money ten years down the road, the answer is no. Notice that the study has factored out the variables of SAT scores, the factor of having the ambition and confidence to apply to the top two tiers of schools, and we have a good idea that the students are very comparable because they were both accepted and rejected from the same schools. Say, both kids almost made the Ivy tier, both got accepted into the second tier, but one kid said to heck with it, it turns out my hometown university is one of the very best state schools in the whole nation (Cal, Michigan, Virginia), so I will just go there. Ten years later, he is making the same money as the kid who went to that expensive second-tier school.
Conclusion: It matters how smart you are. It matters how ambitious and confident you are. It does not matter that you take the final step of spending a fortune to get one tier higher on the college prestige ladder, because the value added by those colleges is not statistically significant for most people. Because each tier of schools has, on average, a smarter/more ambitious/more confident student body than the next tier below it, statistical studies of future earnings will show higher earnings per tier without proving that the colleges themselves deserve any credit for it.