I agree with sixpackgut, but a great deal of Drag Weekers bring trailers for convenience more than necessity. Easier to disconnect a trailer than unload a bunch of stuff from the car. My personal preference is I don't want the liability of the trailer on the drives versus the convenience at the track.

The letter of the rules say that if someone else is carrying your stuff in a trailer, they are a support vehicle, which isn't allowed. We usually have one person in our group who pulls a trailer, which carries generic stuff like tools, jack, generator EZ-up, bbq, coolers and his own stuff, but we keep personal stuff and spares to each car in the vehicle they are intended for.

Grab a couple of cheap moving blankets from Harbor freight. Great to throw on the ground for a nap or to work on the car, great to wrap stuff up in the trunk to prevent damage, and cheap enough that you just toss them away when the adventure is over.