Even the spools made to attach to the precut film have no problem attaching using tape. Really, it works exactly the same. After 5 years of bulk loading my film I've only had 1 roll come off the spool, and that was the second one I ever loaded and it was with a motordrive. I have considered such a device myself, but I have to agree that it's a solution looking for a problem. No reason you couldn't have it custom made for your own use though, just get in touch with someone with a laser cutter to make up what you want. Make up half a dozen and see who else wants one. There's no logical reason for Ilford to make a very niche product for what is already a relatively small part (people bulk loading) of an already niche market (analogue photographers).