Are you sure it's not "exceeding the
maximum reccomend hose bend angle" ?
I have them on most of my hoses. They are like, $3.50 at a store near me, but they are plain. They put them on for me too
Don't think it's DIR, because they can hide corrosion and whatnot.
If your hoses are new, I don't know if I'd worry about it. If your hoses are asold as mine are, and the only reason you have them on is to hold it all together, keep 'em!