Ok, My practice is that if I like something well enough I buy a minimum of 3 yards. If I love it, then 5 or more yds.
My favorite shop has beautiful prints/tone-on-tones in backing fabric (amazing quality) at 108-120" wide for about $9.99/yd. With that, I buy a minimum of 2 1/3 yds. If Hubby is with me he tells them 3 yds. (He's used to fabric shopping with me.
Now to the Wal*Mart issue. The elderly woman at corporate whose "Pet-project" was the fabric departments, died a few years ago when we all started seeing our fabric departments disappear with each new remodeling and being replaced by expanded electronics dept (some MAN thought this up).
A community south of here had a large Menonite community. Their Wal*Mart took out the fabric. The leader of their community went to THAT customer service and told them that although they spend a lot of their $$ there, "We got along just fine before you and with no fabric, we'll get along just fine without you again. Have a nice day." The fabric department was brought back the next week. *s*