Can a unit (position doesn't really matter for this) force SM's to purchase specific items?

Here's the question(s) more in depth. Someone approached me about this, their unit has routine "A&B bag" inspections. A new list just came out. There are certain items on this list that typically come from the Unit Supply Clerk, such as "engineer tape" and "100mph tape", but there are other items listed such as "wrist watch" or "knife/multitool". Aside from the OCIE on the list, it was announced that the unit supply would NOT be providing ANY of these items. It was stated that all members of the unit will purchase any item (outside of OCIE) that is on the list that they do not currently possess. I cannot find for the life of me which (if any) regulation covers this. I've seen several other posts about forcing the purchase of jump boots, or similar uniform items, but those are uniform items and fall into a difference category....Any help would be greatly appreciated.