Worth, if you are not going to can the salsa, you can make it any way you want.
Also, the point of water bath canning is not just to seal the jars. I read every day how people put hot good in jars, flip them to get them to seal and all is well. Nope. Sealing the jar by flipping as opposed to water bathing just seals in any mold spores or other microorganisms. JUST sealing the jar is not the goal. Destroying microorganisms, then sealing the jar is. Processing brings the food up to temp inside to kill any *thingies* floating around in your kitchen that get into the food while you put it in the jars. I'm quite sure you know this.
NCHFP and Ball spend lots of dinero testing recipes so that anyone can make them and know they are safe. Yes, they have a big margin of error built in. NCHFP just released several new salsa recipes a little over a year ago.