Hi and welcome.
Please don't even waste any time on thoughts about those people. They would have issues with many people, and would have such little in their life they feel the need to judge others. They would be rude to many, like people who don't dress well, different races, etc not just you so don't even think twice about them. Its their issue not yours.
My suggestion for any gastric surgery is to get some counseling first, just so you receive all the information before you decide to go for it. I have heard some stories of people going into it without really knowing all the facts. Start with your GP which you will have to for a referral then get as much information as you can. It is not a quick fix, the reality of your lifestyle afterwards can be different but in saying that I know some who have had success but it is an effort after the procedure. I would try and speak with actual people who have had it.