Seriously! It's all about that heat build up. I've had cheap LEDs get warm enough to warp stuff if the glue traps the heat. Good call on the airflow fix.
That thing about LED strips melting foam surprises me. I've used basic cheap ones for years on XPS foam and never had that happen. Maybe it depends on the density of the foam or how you stick them on. Good air flow around the strip seems to fix most heat problems. I just think the melting issue gets blamed on the lights when it's usually about how they're put in.