I didn't suggest this was a ploy, I'm confident that the person in question has only the best intentions. I don't think it's unfair to step back and ask what the right approach is, intentions aren't always enough.

For instance, the issue with flammability/melting and also microplastics contamination is real and worth asking. I wonder if using these bricks as building foundations or something might not be a good way of solving both problems at once. However, that's an idea that would only arise if we ask pressing questions in the first place.

It's not the ideal building material and it's a plentiful resource that would otherwise end up ideally in a landfill but likely along the side of the road.

From their perspective it is a good use of something that might otherwise be litter.