I don't see any reason to get rid of cut color unless it is burned out or faded. I save every cut of color from every show that meets those criteria. So, I have a large filing
system where we store cut color and uncut sheets. When I get the paperwork for a new show we pull color from
stock first and then buy what we need to complete the show. This saves quite a
bit of money.
You have to consider that there are colors that are not worth saving like deep blues that tend to
fade quickly. However, I see no reason for a school, community, or
regional theatre to just toss color after every show. it may be a consumable, but not every cut is single use.