Never had a problem with them in 33 years of regular travel. Inbound have regularly used Boston, Chicago, Newark, Washington Dulles, Miami, Houston, LAX and SFO over the years with many visits to each. Always strike up a conversation and always have been courteously dealt with.
I now have a 3 year old granddaughter born of British parents in Houston. When asked for the purpose of my visit I always say "to visit my red-neck granddaughter". Always brings a smile and a chat.