...on buying all CUU. Wouldn't they be just sucking up ever single claim near us instead of letting Marko muck around in there?

Teck did stake around 78,000 hectares in one night last April. I think that was a good indication of their intentions. Marko is just getting lucky picking off a few on the fringes. It's possible, I suppose, that the aerial showed some potential and that's why CUU bought them from him.