Old but relevent.

They may not be a travel agency, but they DO demand a travel agency commission from hotels they book for.

No, they do NOT have a direct connection with most non-chain hotels. The reservations are often FAXED to the hotel; and sending a fax doesn't necessarily mean it was received, let alone read & processed by the hotel. Sometimes even the chain hotels in-house reservation/property management system is not electronically integrated with the chain's system, instead relying on a manual re-entry of reservation info; a system wrought with opportunity of error.

Sometimes they're not the cheapest either. Do your own research & compare.

I use the online booking agents primarily to identify what properties are near my destination, then check the individual property websites and even call directly to secure the best rates.

Buyer beware.