Everyone will get a 'cut' from the sale of Thistle merchandise.
I'm not an expert on retail sales but take a top on sale with Greaves for £50 as an example (figures are simply guesswork). The manufacturer will make and distribute the top for say £30. Add on say £5 paid to Thistle so Greaves would pay £35 giving them £15 per top to cover their costs.
I doubt Thistle are going to sell enough merchandise to be able to demand up front payments or big royalties. Added to that, the big kit suppliers (Adidas, Nike, Puma) want to shift huge numbers so won't want to offer bespoke kits to smaller clubs like ours so we tend to go to smaller, niche firms like O'Neills which until recently were only known for making kit for gaelic games in Ireland.
I reckon the stuff they produce for Thistle is as good as anything we have had since the Puma days and a far cry from the TTL stuff.