Don't let bike snobs ruin your riding. If you call a shop ahead, and ask for the cost and a time you could get "fitted" to your bike, they should be able to get you in. If not, don't go back, or better yet, let the management know how friendly (NOT) his employees are. I walked in off the street with a used bike I had purchased, and the team there (NITRO, Oahu) fit me for free.
Let them know you are a new rider and are seeking guidance. My experience is that most guys/gals working in a shop are very knowledgable, but may have a bad taste from too many ego's spouting off at them. Remember everyone has an opinion and is entitled to it, take it with a grain of salt. Politeness begets politeness. There are more riders out there willing to help than snobs -