It's to do with the age of the rabbit and the point it was in it's shedding cycle when it was killed.
Really, really good rabbit skins won't shed, but those are called Prime skins and they're from rabbits about 6 or 7 months old. Basically adult sized and furred but not moulting. Four month old ones are lovely skins and fur but soft, and really only for inside out courrans or lining mitts, pockets, gloves, muffs and hats.
Rabbits, iimc, moult three or four times a year, and if the hair is already coming out when it's killed, then tough luck, it's not a 'prime' skin.
Difference between buying a furrier quality pelt or coat and a generic one from a chain store back in the late 70's early 80's when coney skin jackets were really in fashion.
cheers,
Toddy