I race my own boat and on others. For regular rides I try to pick up the bar tab every now and again. Bring a bottle of booze, or some jerky or chips. I know exactly what the skipper puts into a racing boat, and it's a lot. Does it make a difference in the $10-15k yearly budget? Not even a dent, but I know the skipper appreciates it.
On my boat, I supply food, drinks and maybe a snack while on the boat. I don't do the small club races, or weeknight racing. For regulars, I'll have tech shirts made and hand those out (like I have any regulars...).
I believe there is a minimum you should do, then if you win, you should do more. Reward the extra effort. When we won DTB, I went ahead and picked up the hotel room for the crew. Won coastie cup, and bought lunch/drinks for the crew. Seeing as my crew is in their 20's, a bar tab can be $150-250 without much effort. Just part of the game.
I'm not sure how to get regular crew and keep them. I've tried everything. Food, hotel, booze, clothes, tech gear, new sails, etc. And still, I've never had one crew come out to roll on some new bottom
paint. I've even offered to supply the crew with matching spray tops or foulie jackets. I get nothing. Hardest part is to get people to commit who have the same goals you do. Everyone seems to have better things to do.