I'm a fussy eater and I hate it. I don't choose to be the way I am, really, life would be much easier if I wasn't. It's not for attention or to be awkward, it's just the way I am. I believe it's a combination of being terribly ill with salmonella from drinking raw milk as a toddler (Mum borrowed it off a neighbour and didn't realise it was unpasturised), growing up with a fussy Dad of the meat and two veg only variety and having an impatient Mum who tutted and huffed and told me off for gagging at certain foods. 7 years ago I would only eat plain chicken, sausages, joints of beef (no mince), potatoes (no rice or pasta), peas and raw carrot. Fruit and yogurt etc. fine but no sauces, no gravy, nothing savory creamy, no spices, onion, garlic etc. It made life terribly difficult.
I'm a million times better than I was due to a rather marvellous, patient and dustbin like OH. He made me feel secure and ok to try things, and if I didn't like something then fine, more for him! For example my journey of going from plain chicken to 'normal' fajitas involved adding a bit of fajita spice to grilled chicken, then adding a few cubes of tiny cubed red pepper that only I could cut, then adding a bit of tiny cubed onion that only I could cut, then gradually making the veg bigger, then adding to a wrap, then finally adding lettuce and now I eat fajitas like most other people. That process took about a year. After 7 years together I now eat most things, all veg except cauliflower, all meat including mince (still not a fan of fatty wibbly meat but I think that isn't uncommon), pasta, rice, spices, whatever. The only things that I really can't eat are raw tomatoes and gravy/stew type things. And filter feeder seafood (should not have studied marine biology!)
Having people tut over your food choices is not helpful, infact it makes me regress completely and not be able to eat anything at all. For example, we went for a family meal at a pub and everyone had a roast dinner with veg in big bowls to share. I went to put a pile of mangetout, carrots and broccoli on my plate and my Dad said infront of everyone 'its not like you to eat veg'. I was terribly embarrassed and couldn't physically eat anymore to which of course caused my Mum said I was just being fussy and silly. Just leave people alone to eat how they want to eat, if there is someone that you know who won't eat certain foods then why would you invite them over and serve something that they wouldn't eat? That's passive aggressive behaviour if I ever I saw it.
Having said that, I totally agree that being rude about food is not acceptable, e.g. bleugh, how can you eat that. But that's not because the person is a fussy eater, it is because they have no manners.