I so agree about not settling customers with plastic waste. But also am trying to eliminate it on my end as well; adhesives and label backing sheets are generally not recyclable. So we end up with extra trash that way.
I was thinking about this issue today, the fact that those backing sheets are coated in plastic, and actually am going to try the following out.
I think the backing sheets might make an excellent mold liner that's potentially reusable due to the plastic coating on them. I already reuse my freezer paper multiple times until it's no longer functional. I simply wipe it the freezer paper clean with alcohol & a rag, then stick it back in my molds. Even parchment paper is loaded with dioxins - if it's the white stuff - so no one method / material is perfect at this point. Good reason to use unbleached parchment paper in baking as well.
I also don't throw out the scraps surrounding the labels to reduce waste. I cut those bits into strips, and then smaller pieces using my Fiskars cutter - like one someone who is a card maker might use - and use those scraps as safety seals on my salves, body butters & other skin care products. My intent / train of thought is that this too reduces overall plastic usage because I it prevents me from using shrink bands of any type. I have an envelope full of these pieces. I just cut this stuff up when I'm sitting & watching videos on my laptop & apply the safety seals then as well. Those bits & pieces come in handy for many things.
For label sheets which are not so usable for this purpose - such as circular label sheets - those are the ones I am thinking which might make great mold liners. Then I will think of another use for them once they have outlived their lives for that purpose.
Every little bit helps in reducing plastic consumption & reusing the plastic we already have in as many ways as possible.