Haven't bought a new Browning with a decal on the barrel. Is it easily removed...? Me...I would remove it.
My BPS had one, it was not stuck well at all, I peeled it off, I don't think it was a real barrel sticker, more of a hey you bought a Browning type sticker, LOL!
I believe my BAR had one of those on it when I got it. I pulled it off. It clashed with the camo dip. ;-) I have seen a gun that had evidence of where such a sticker _used_ to be. Don't recall whether it was a Browning, Winchester, or what, but you could see a difference in the color or reflectivity or something of the bluing there. It may have come off if a person would oil the barrel. I don't know; didn't buy it.
I left mine on my 525 but if you shoot a lot and the barrel warms up enough the edges of the sticker fold up. I peeled the sticker of my GP sporter and stuck it on a mirror in the gun room. Might stick the next one on my safe.
I peel and toss. They come off very easily, but still, I can see issues with them being allowed to remain on the barrel, from the heat of the barrel making it difficult ro remove down the road, to possible rust issues. These were never meant to remain on the barrels, so I just take them off and toss them in the trash. If people really need to know what I am shooting at the trap fields, they can ask. And if Browning wants me to advertise for them at the trap fields, they can pay me to do so.