For F Connectors and RJ45s, we use the Ziploc screw on containers. You can carry them in a tool bag, and if they get crushed the lid doesn't pop off and explode everywhere. They come in two sizes and I got them at Wally World for like $2.00 for a set.

I think the Rubbermaid thing was out of desperation. He usually does my central vacs, but I was having him do more and more trim outs. The other techs went to HD and bought a Husky bag that has a seat with a zipperd pouch underneath. They keep all the plates and jacks in there, and just carry a small tub w/ tools and connectors. They bought theirs, and I wouldn't buy one for him, so he improvised.