I got the same thing at our first visit to the local MCHN, when DS was 5 months old. She told me that by feeding him to sleep, I was just making it more difficult for when he was older, that if he wouldn't self settle, he would always be a bad sleeper...on and on she went..

His 9 months today, and we still feed to sleep. (He has self settled a couple of times though)
That day I came home from the MCHN, I was crying, and had a chat with DH who reminded me that I was the one who was getting up to DS during the night, I was the one who was looking after him during the day, and I had to do whatever worked for us, not what the MCHN thought should be working for us...