Corporate travel policies usually have agreements with certain hotels and we are told to book at those. So even if a "luxury" hotel might have an equal or slightly lower rate published, the company gets an overall rebate on total annual spend which can lower the published rate beyond what a biz traveller can see.

Also, I worked for one company that wouldn't let us stay at the Ritz, even if it were the same price or lower than others because our clients (to whom we expensed costs) perceived it as more expensive.