Gosh, I remember having that problem... in reverse!
The company where I worked never paid their small suppliers on time, even if the invoice was only for 15 euros without VAT: they would have to chase us for a minimum of 6 months.
On the other hand, big suppliers, with invoices for tens of thousands of euros, would get paid every month: 'we' couldn't afford to lose their business!
I wasn't in the department dealing with suppliers, but some of our small suppliers were also our clients, so they would call me to try and get their invoices put to the top of our 'to pay' pile. The other problem they had was that when they called to chase, they would systematically be told that their goods hadn't arrived in our warehouse... when in fact they had already been forwarded on to our clients (OK, some of these were bad payers)!!!
As to consumables such as paper for the printers, cardboard boxes to pack the goods, ink and toners for the printers, pallet film: the companies who supplied those would ask us to pay in advance, because we had been such bad payers in the past... So sometimes we would be unable to send goods to our clients, because we had run out of cardboard boxes, but we would still be sending them invoices for the goods which were sitting in the warehouse, because we needed the money in order to buy cardboard boxes to pack the goods!
The owners of the business paid themselves very high salaries though, + company cars, laptops, smartphones, trips all over the country to visit existing and new clients, with stays in posh hotels and meals in expensive restaurants...