While i don't always wash my fabrics before i do a project - i ALWAYS wash any cottons and batiks before combining them (washed separately of course). I've never had a bit of trouble combining the 2.

I say that guys was just trying to get more sales. I use both types of cottons all the time. never had a problem. I just try to make sure the they feel similar. just for quilt integrity. dont want one fabric to rip or what not while the others are just fine. have had that happen on one quilt i made and it was only one of the 4 batiks I used with two different regular quilting fabric.

I do it all the time (as you can see on my avatar).

Don't worry about the quilt police.... mix the batiks & cottons.:o I do it all the time.