1. Private negotiated rates - medium-large companies have bulk rate discounts individually negotiated with various chains that can be integrated into the search flow. 2. Policy management - rules like C-level staff can fly business class, or regular employees may fly premium economy for flights over X hours, etc. 3. Expense report integration.
These things are important enough that most large companies are willing to subject their employees to a subpar travel search experience to get this. (I work for a Concur competitor but freely admit that our search experience is also subpar compared to consumer sites).
I travel pretty frequently so I often just call American Express (who acts as a Concur reseller for my company) directly to do the corporate bookings rather than futzing with Concur. I usually find the route I want ahead and then call Amex to price it out/book it. American Express is great — tho my company is big enough to have dedicated CSRs for our account, which helps. Concur is just frustrating.
That said, I will say that the worst parts of Concur are usually employer-made decisions. If your employer has really restrictive travel policies, that makes the Concur experience even worse. For instance, I’ve had the system insist I book an indirect flight that costs more than a direct because of how something is coded, with no way to override. My current employer has very decent travel policies so that’s not an issue, but if it is, it makes the terrible UX and bad search even worse.
And, yeah, if I did more traveling I'd probably just call up our travel agent. But I'd still be on the hook for cash expenses.
It does have some competition when it comes to expenses: Expensify, Netsuite, Salesforce and homegrown stuff come into mind.