I can’t answer the question of whether feeding the birds is a harmless way to get people to care about wildlife or a if its a tragedy. But of all the harm that feeding birds does or might do, it looks like we can cross pesticide exposure off the list.
The American Bird Conservancy had a lab test bird seed from various sources and found either no pesticide contamination, or levels below those believed to harm bird health.
The nice thing about this study is that it included seed from WalMart, Home Depot, Lowes and Target, places where the average bird feeder might purchase seed.
The actual report does not appear to be available. I’ll keep looking and post when and if I find it.