I never said there was a chemical change, this is twice that you have said that. Secondly, I am fully aware of what "silica" is and where it comes from, alas I was the one who mentioned it in the first place. Glass (some glass) is silica based and so is "silicone sealant".
2 textured surface will have better adhesion if the textures match. This simply equates to surface area and can be looked at from a MACRO standpoint (surface prep) but more importantly from a MICRO standpoint (surface structure). Acrylic and glass are different, all the DIY sirface prep in the world does not change that.
I don't ever "wonder why" rough metal holds paint better than polished metal, I know why.
The Saran wrap was a bad exemple and should have been left out, I was trying to illustrate that some materails stick better to others. I am aware that saran wrap relys on static.
Your teflon example illustrates my point. The glass and acrylic have to different surface structures. The silicone has better adhesion to the structure of glass. This is not a "surface prep" issues, it is the surface structure on a molecular level.
Teflon? Yes I know how teflon works. It was my choice as a research project back in the college days.
How did I ever get the notion that polyurethane will not stick to PVC? I have pumped millions of pounds of SINGLE and PLURAL polyurethanes. General polyurethanes don't stick to PVC, it's that simple. Are there polyurethane products used to bond PVC, YUP! There are tons of them, but they are highly modified "glues" not straight diisocyanate-polyol blends. Some of these "glues" form a joint stronger than the PVC itself. Many are designed to alter the surface structure of the PVC (chemical bond) as well as add body to the joint (unlike a water thin solvent).
In any case this has moved way past the scope of the question at hand. The bottom line is that 100% silicone sealant sticks to glass far better than it does acrylic. You can make a "better" acrlyic joint by roughing up the surface, but the adhesion will still not be as good as that to glass. Increasing the surface area of the joint will also help.