Yobit is not a scam for sure, its in my opinion even very trust able and I never had issues with them when I worked with it.
Its trusted by a lot of people and there is also a campaign from them, they can be trusted and these days a lot of people still use it.
its trusted by a lot of small accounts that surprisingly also are around their icos, a campaing used by heavily promoters that are involved in the icos, and a lot of people is attracted by them, hence why some people use it, yet most end in disappointment.