A neighbourhood school wants to start an Environ-friendly awareness and action project for the children. The idea is to collect plastic water bottles (preferably of the same size and shape) and stuff them with non-bio-degradable dry wastes such as polythene covers, chocolate wrappers, biscuit packet wrappers etc. There are a few online articles, (ex: here and here) about bottle bricks or eco bricks , which refer to the trash-stuffing practice, and there are numerous others which talk about filling sand (not the point of this question). There have been reports of using them for structural use (such as building) or other non-structural uses. It is hoped that the bottle bricks made at the school can be used somewhere like that or to be sent to environ care agencies that can use them.
Are there any demerits to this idea ? One possible demerit, I had thought (before learning about the above links on bottle bricks) was: In case the bottle is not used in the brick form after stuffing, it may make the plastic bottle tough or impossible to recycle in traditional ways. I hear, usually, the plastic bottles are crushed, to make pellets and then recycled back into bottles. Stuffing the bottles may make crushing-pelleting route difficult ?
Are there any special aspects that should be taken care of, before taking up this stuffing project ?