I agree with you, they really have no idea.

I was adopted at birth by a woman in her 40's who was very well off. The dad I grew up with had kids, but they were already past 18 and had moved out. I was pretty much an only child. The thing is, it's taken a lot of time to process how I feel about everything. Even though things can be good for the adoptee on a surface and basic needs level, I think on some level subconsciously or even consciously you will feel like an alien to some degree. There is no reference point on your physical appearance. Over time, you will begin to wonder if some of your personality traits come from somewhere besides your adopted family. It's a very complicated thing. Will your adopted parents resent you for reaching out to your birth family?

I'm in my 30's now, and it has taken me this long to understand enough about my feelings to start the process of finding my birth parents. I think my birth mother allowed me to find her through the courts, but if this ends up not being the case I assume it will be painful, no matter how much I think I'm ready. People that aren't adopted really don't understand any of this and that's not even mentioning the abandonment issues, or "fixer" personality types many of us go through.