I have no insight as to what is officially tolerated. Feel free to ignore the existence of the many web sites and discussions here on flyertalk that detail the phenomenon here in the USA and elsewhere.

Some companies have tried to capture this revenue by offering you an upgrade at time of booking and perhaps at the front desk as well - Hilton Hotels has something called NOR1 for example. Presumably, a suite upgrade when regular rooms were available would be followed up with a "why did you do that?" were the fee not collected for the company's benefit rather than the clerk.