Most of these don't really bother me, which is odd because I tend to go straight for snark/sarcasm in general.
1. I know how you feel. - doesn't bother me even if I doubt they understand - they're just trying to be sympathetic
2. Do you or your husband have food allergies? mostly legit (albeit somewhat invasive question, but doesn't bother me
3. But he looks so normal! these kind of rude comments I tend to ignore, but take my lesson about that person's character
4. What in the world do you feed that poor kid? again, this one doesn't bug me because at one time, DS had clinical reactions to over 30 foods, I often wondered it myself! If my kid had been PA only, I would have just assumed they were trying to sound relatable/sympathetic and let it go.
5. I made this for you. It doesn’t have peanuts (or milk, egg, gluten, etc.) for something I'm taking with me, I usually say thank you and then just get rid of it at home later. Luckily, I haven't had too many times where I've had to refuse someone who had tried really hard to make something special for me. It's sucky when it happens, though.
6. He’ll outgrow it, right? Again, I feel this is a somewhat legit question, so I usually just answer as honestly as I can.
7. They can cure that allergy now. Or: Did you ever try . . . ? See #6
8. He’s going to have to get used to it. See #3
9. I feel so bad for him. I understand they're trying to be sympathetic
10. God never gives you more than you can handle. I hate platitudes like this, but try to remember it's usually said when the person just doesn't know what else to say and feels the need to say something.
The worst comment I ever had to deal with was when DS's kindergarten teacher (private Christian school) told me that every day in class they would pray that God would heal DS. Without getting into a theological argument with her about the way I believe God works, I did point out that it was very insensitive of her to constantly point out his medical condition that likely wasn't going to improve any time soon. I asked her if she would pray every day for an amputee that their leg would grow back? I told her she needed to find something less disingenuous to pray for.