Scott,
Yes, HP is not currently offering the VI Foundation license with their ESXi option kit. However, I believe they have an unlicensed option kit available as well. That is, you buy essentially a media kit (USB key with software, documentation, etc) along with your server, but there is no VI license. Then you can buy the VI Foundation Acceleration kit separately (also available from HP, I believe) which gives you the licenses. I can verify this.
The USB kit in the HP option kit do mount internally on the motherboard. HP has internal USB connections on all the qualified servers.
The HP image of ESXi does have customizations around CIM (Common Information Model) which will give you HP-specific hardware management info.
John