What Makes a Quant Method Quant?

The main method that I use day-to-day is survey methodology. Anything that really produces data that you can put a number to and percentage to or frequency to can be considered quantitative. There are also things like you mentioned with sample size that do tend to gravitate towards one or more of the methodologies. It's all about representativeness and trade-offs in terms of how much resource you're willing to put into collecting the data.