Originally Posted by
paperwastage
there's also a minute possibility of getting a BULK fare that may change MQM calculation
(note that most BULK fares aren't sold standalone as a flight by the travel agency, usually sold via a bundle, eg with a cruise/hotel)
Bulk Fares & Perks (or lack thereof...)
note to mention the mess of getting a refund from OTA (see last year, OTAs can leverage additional fees / timelines before giving you the money back)
https://www.flyertalk.com/forum/32442696-post287.html
this happens more with the 'questionable' OTAs you'll find. If you go to any of the major ones (Expedia, Priceline, etc) they will be sourcing rates directly from the airline. If you find some amazing, too-good-to-be-true price on Kayak from an OTA you've never heard of, they are probably scraping package/bulk fares and adding a slight markup so they still appear cheaper in kayak results