Dispensaries/producers mixing extracts? Trim content?

I recently heard from someone that it's common in the weed industry and in state dispensaries to mix waxes and sell that as its own "strain". For example, Garlic Breath is typically a cross between GMO and Mendo Breath, and I'm told they'll just mix GMO and mendo together and call that "garlic breath".

Also heard that it's normal/common for extracts to be cut with trim, even in dispensaries.

Can you guys shed some light on if you believe this to be true? It'd change how I interact with cannabis if so.