we all have things we are comfortable with. They may not have been easy at the start (reading our Bible every morning, being a camp counselor, etc.) but once we have formed our habits we know what we are doing. We are comfortable. It is at this point when we can get stuck in a rut and not be accepting of things that other people are telling us or realizing that we have to still be present every day. I think this may have been what happened at Lystra. The people there were super comfortable with what they knew, and thus they had a hard time accepting that Paul and Barnabas were not Gods. it was easier for them to latch onto something they could be comfortable with than to accept something that they could not.
It is completely opposite to what the people in Pisidia did, where many ended up believing. However, Paul and Barnabas react the same when people believe and when people want to drive them away: they continue to press on to spread the Good News. They did not remain in comfort if they had it, they moved forward into the plans prepared for them.