I find that its about half and half these days. HK bags (or the plain bags with HK sticker), or plain bags. I do think its pretty funny to get something like I did recently: one MR takedown pin detent. That piece of metal is so tiny that the 5x10" HK bag outweighed the part by a longshot.
If it's new, it's new. HK baggie or not. Some are just obsessed with HK baggies.