I guarantee you, in a large enough organisation, there will be exactly one approved pencil supplier. That's how corporate purchasing works.
There's a lot of cases where this actually makes sense for compliance, support, and service level agreements between your org and the vendor's among many other cases. It just gets annoying when you absolutely cannot buy coffee beans from shop B on the team consumables budget because we have an exclusive contract with shop A.
In a governmental organisation, you might even need a public bidding process for any supplier contract big enough to cover printers and their ink/toner, as well as a support contract if something breaks.
Yeah, and this is fine. This is basically what I meant, a company can just select and potentially make a contract for a specific application. That's how it works for everything. My point was that there doesn't need to be the unique single global vendor/application a priori.