Correct. In fact many, many companies have ASNs. Little companies all the way up to large ones. The key difference for an ISP is they allow you to route traffic through them. Almost every company that has an ASN blocks traffic from being routed through them, assuming they know how to configure that and that they have different peering points. Valve most certainly does not allow you to route through their network, they already have enough traffic just doing their own CDN stuff.
Correct. In fact many, many companies have ASNs. Little companies all the way up to large ones. The key difference for an ISP is they allow you to route traffic through them. Almost every company that has an ASN blocks traffic from being routed through them, assuming they know how to configure that and that they have different peering points. Valve most certainly does not allow you to route through their network, they already have enough traffic just doing their own CDN stuff.