But certanly there are some that are sponsored now days nothing is for free and top sports are sort of cash intensive
I can tell form my experience now days some top slalom paddlers are paid by the manufacturers to race their boats and act as co-designers of the new boats .And most manufacturers have at least one on the roll ,but some have 3-5 depending of the categories they suply most.
As the top paddlers change all the time lately the price for sposoring 'works' paddler droped a lot back in the late 80's early )90's top slalom paddler was paid by a manufacturer cca 50 $ per boat produced by that producer which made 400 boats per year at that time ,for some of the lesser races even the organisers paid for the top paddlers to come ,that is most likely still done today .
Most of my kayak buiding friends who have ''works'' paddlers admit that it is a bit cheaper now than it used to be,as a sort of a standard now they suplly 3 top notch boats per year to a top paddler & if they co-sign on a design small designers fee 20-40$ per boat produced