Yes, your not fusing to protect the lights, or even the battery, but the wire. If you don't fuse. Then the wire will act as a fuse. It and anything near it, will get quite hot, before it burns through.
I installed mine in my 2012 Lariat Screw just as OP explained. Very pleased with the results and the way the lights work with the cargo and interior lights. Took about 1.5-2 hr to install below my Peragon bed cover.
u had 1 amps going for about 5m of led ribbon then switched to a 2 amp b/c the 1 amp kept buying out
so far its been working.
2012 F150 Fx4 Red Candy Metallic, Ecoboost, Fx Apparance and Luxury Package, Nav, Sunroof, BackflipG2 Tonneau Cover, Spyder CCFL Hallo Headlights, 6000K HIDs in Headlights and FogLights, OnBoard Dash Camera (DR400-HD II), Viper 5901 with SmartStart and GPS