if it really makes no apparent difference to you then I guess Google has decided I'm somebody who cares about using the - operator and you're not and for this reason serves me greatly different results because shirt -stripes is quite different from shirt with stripes or shirt without stripes.

not that there aren't a couple of striped shirts in there, but nothing like otherwise. So I mean, there is an extremely apparent difference from me, even though there is not the perfect result you might wish for.