Cheap does not always equal substandard or shoddy.
But, sometimes it does mean buying in bulk.
You can still get wholesale or warehouse prices.
As stated above,
https://marshalldrygoods.com/ is a good place to visit.
One of my fave places to buy quality, name brand, modern quilting fabric is Textile Collections:
https://fabric4less.com
the catch....you have to buy most fabrics by the bolt.
This place also has cork fabric (fat quarter size pieces-not by the bolt), polar fleece, flannel, home dec, and other fabrics, just like MDG
also, for just a bit more,
https://www.quiltedtwins.com/ is a fun place.
and the hunt for clearance sales is always a fun challenge.
edit: oh, to see the prices at Textile Collections, you do have to register...create an account, but it's free.