If that lot it is being plastered over then they will almost certainly be covered with a plastic capping in due course. I can only think this is a temporary arrangement until the electrician has bought some more capping / found the time to fit it/ finished running cables in the vicinity. However, it isn't compulsory that cables are capped (at least, not to my knowledge). The plastic capping is only really there to prevent damage whilst the plastering is being done.