I've also noticed that, and I always recommend various self-learning apps where you can even earn a few sats while educating yourself with Bitcoin knowledge.

Lederhosen

bitcoin

What fears and concerns have you encountered when speaking to merchants?

The biggest barrier I've encountered is knowledge. People don't know what bitcoin is. They also don't know what to do with it. They usually link it with pyramid schemes and other "get rich quick" scams. 

This is mostly related to the frequent news related to cryptocurrencies in general and how the press "paints" this stuff to the public. 