Primer surfacer is usually the color it is. If you see a mix of black over spray, that is usually a guide coat for sanding.
Now sealers are a different story. Tintable sealer can be made about any color you want using a compatible paint to tint it. There are several types of primers and sealers and for some one that don't know get info from paint jobber on what is best under coat for the paint you use. There is a lot of difference between each kind. Some are self etching and need no etching primer some primer surfacers need etching primer under them and sealer over them. Some epoxy primer/sealers do it all in one step. From bare metal to prime to sand then paint. DDL K200 is good for this especially on a striped car. Especially for some one that doesn't do it all the time. and is going to stretch the paint prep out past a day or so. If you don't need to block a majority of car DDL DP epoxy sealers are good. They need no etching primer or sanding between sealer and color coats, but there is a time limit from sealing and painting. The bare metal needs to be finished down to a 240 DA sanding though. A big labor saver.