Show me a gel/spray that isn’t. They are all going to be some form of ‘sticky,’ which means some form bonding, likely protein or carbohydrate based. Either of those will take oil from your hair when removed/washed off, and are obviously interacting with the keratin itself to create all the stickiness between hair strands.

I haven’t heard that before but I don’t work on hair care products very often. Benzyl alcohol is used as a preservative in lots of cosmetic products though. It can be considered an allergen for some people, but overall it’s pretty safe (as far as we know so far).