The reasons for NOT tracking are myriad: First, you’ll engender goodwill with your supporters. Second, you may not imagine your organization to be the likely target of ransomware or of a data breach, but the less data you collect, and the less you share with outside organizations or companies, the less likely that your supporters will be affected. Third, data privacy laws vary across regions, and we are in a time of rapid change with respect to those laws. Minimizing data collection and retention can help ensure you’re complying with those laws.
Tons of nonprofits give extremely little of their donation revenue to the actual claimed cause while their execs get fat paychecks. For these non-nonprofits, tracking people is right up their alley.