Yes.
Most people have a harder time measuring 1 oz. per gallon than they do measuring 1/4 cup per gallon, and a lot of people will tend to overmix the higher concentrates (that 1 oz per gallon doesn't really look like much, I had better add more!).
Then there's the marketing angle, where the beancounters figure out that they can make more profit by selling a quart of weak solution more often, than they would by selling a quart less often.
Jon