Bryan, to quote your opening sentence: "When I became a shopper I was under the impression that Market Force was the biggest MSC in the industry. Now I find out they aren't even in the top 20 of companies."
They *are* the biggest MSC. They never claimed to be the biggest market research company. You're comparing apples and fruit.
The list on which they are #21 is a list of market research companies.
GfK is based in Germany; I expect their revenue information may be worldwide. Maritz has irons in a lot of fires other than Mystery Shopping. Their combined market research revenues may exceed Market Force's but that doesn't prove their mystery shopping revenues do.
I guess I'm not getting your point and why you felt the need to try to denigrate them for failing at something they never aspired to or claimed to have achieved.
There's a lot more to market research than mystery shopping.
It's notable that the number of us in the forum who said we shop for Market Force is almost double that of the next-highest company -- about 1100 to about 6 or 700 if I remember right. Not a precise survey, but indicative of something, and it's not that MF is the 21st ranked mystery shop company.
Time to build a bigger bridge.