I haven't seen bricks, but they do make recycled plastic 'lumber' primarily for decking. It is about twice as expensive as wood, but it doesn't need to be sealed and lasts longer. Its a legitimate use, but only financially feasible because of the massive subsidies to recycling. Now they have mountains of plastic, and still can barely compete with lumber on price.
Yeah but your hazard insurance would sky rocket because your house could melt on a real hot day.
Don't look now----but--Polar Fleece is made from plastic bottles. I have always wondered if your Polar Fleece jacket would melt onto you in a fire.