Depends on how you look at it.
lets use a full truck wrap for example. Cost is $2500 to $3000.
You take pride in your truck, you attend shows anyway, you love being unique, so you get someone to wrap it for you for free if you promote their logo.
In the logo, you call up Fuel Wheels, Nitto, Magnaflow, tell them for free or discounted gear you will add the logo onto the free wrap. Simple, even if they give you 50% off (you would probably add anyway) they get seen, logo placement, you get the product for free or discounted.
Now look 2 years later, you add a portfolio of show what you did, etc...you want to build a new truck. If you go back to that vendor, after solidly promoting them for 2 years, they offer it for all free this time. You build a cool truck, for a fraction of the cost for add-ons. Its a win win..sure you sometimes have the cash outlay for gas, etc...but you build a relationship of networking.
Your a small drive form SEMA in Vegas, a majority of the trucks built there are with help from sponsors. If they aren't, they are there networking TO GET sponsors.
But you have to stand out in the crowd when approaching a vendor. They get thousands of request weekly, or annually for free stuff.
Show them their investment in YOU has a return.