Most town centers did not have chains open in them, but the stores in them still died because people preferred shopping at big box stores 2 miles away.

A small college town with a reputation of rich kids going to it is probably going to have an outlier amount of single people with extra money to throw around little shops. If they have families and start budgeting, they will be off to Costco and Walmart and Target to save money like the bulk of the US.

This is an understandable sentiment, but I do not think it applies in this case. In the case of Ithaca, most single young people live closer to the colleges, and drive or bus to the chain stores.

The actual town, I think, survives on the individual shop mentality because the physical layout of the town. The Ithaca town square is physically designed to be the physcial, social and cultural center of the town, which allows the shops there an advantage of being a center of the community, completely surrounded on all sides by walkable residential living. This gives them a competitive advantage, that lets them compete with the bigger box stores which require taking a bus or car a few minutes downtown to arrive at.