They've had blue on their kits, they don't kick up a fuss, it is just a bit small time as you said.
Long before we had this tense rivalry, people stood on the Kop together, would go watch the other team when the other was away, it was part of tradition. Personally, i can't stand them, but it's a colour.
You're right though, they don't own the name "Liverpool", they don't own the Liverbirds and they don't own the colour red. If we came traipsing out in a full red kit, then yes, i'd be fuming, but a tip to our history which existed 16 years before they even wore red.
Just backwards, enjoy a nice touch by our manufacturer, who actually cares about the club.