You don't have to buy a single reloadable cassette if you have a source for empty factory cassettes. Scour your city's one hour labs and take the empty film cassettes after the color film has been cut off for processing. It's trash to the lab, so if you ask nicely they will happily give you all they have. Then pick over the empty cassettes, discarding any that have dirt, dents, or damaged felt light traps. Then, using your bulk loader, you can simply use masking tape to splice your fresh film onto the little stub of color film they leave sticking out the slot. You need to make the connection pretty flat so it slips in without jamming. I've been doing it this way for twelve years over hundreds of feet of film without any scratches.
When you are in the darkroom to develop, use a beer bottle opener to pry open the bottom cover to remove the spool. Every cassette only gets reused once to ensure a fresh light trap.
Using this method it's literally impossible for the end caps to pop off or come unscrewed, since it's factory crimped steel. There are only TWO caveats...
1. You MUST mark the outside of the cassette so that you know the true loading is not the factory label. This includes masking over the DX markings if you have an automatic speed reading camera and the speed is not correct.
2. Until you get good and confident about the strength of your splicing, you can't forget the length of your roll or wind-on too strongly at the end of the roll, or else you may tear your masking tape connection. Then you will simply have to have a changing bag and a light tight container with you to unload the film from the takeup spool. When I know I'm at the end of the roll from long experience I don't try to force another frame, I just rewind it.
When I can't find any more empty factory cassettes, then I'll unwrap some Kalt reloadables I bought in the 90s and never used. If you think this sounds sketchy, imagine how many gun enthusiasts reload previously fired shell casings! After a few powerful reloadings the brass can break open in the worst kind of way! Reloading film cassettes is a safer proposition.