My opinion from 25 years of horse ownership -- vets are the only race track entity that are guaranteed to make a profit from the sport of kings. Owners are definitely not. Trainers, Jockeys, Agents (Bloodstock and Jockey), Breeders, Pin Hookers, Race Track Operators, Bettors, Publications, etc. -- No.
Used to be you could expect a monthly bill for training and vet service to be around $3,000 per horse for many years. Now, I am relieved if it is under $4,000 (major southern California tracks). Most of the increase is from the vet bills.