With Sandstorm, we could actually get that effect on-prem. Since no technical expertise is needed for deployment, and since the security model is so strong, and the IT department will be able to manage resource quotas on a user basis rather than an application basis, it's actually entirely reasonable that people outside of IT could be permitted to install software without IT approval.

Granted, it may take a while to convince IT people that this is OK, but fundamentally they have every reason to prefer this over people cheating with SaaS.