I am a frequent flier, usually acquiring over 100,000 miles a year in flight miles. Its sad that the state of human interaction has been reduced to your experience, but I can tell you I have always made it a point to say thank you, but rarely do I get a ‘your welcome’ in return, instead they are already moving and pointing their attention to the next passenger, thereby not noticing that I’ve said thank you. When I board a flight, FA’s are usually too busy talking to each others to notice if I greeted them, often time about their dislikes about their job, company rules, pay, and other grievances about their work, nothing says “good customer service” than complaining about your job within earshot of passengers. I dislike watching FA’s use the lavatory while taxiing knowing passengers can not, to me it sends the message that we are ‘exempt’ and ‘special’, regardless of FAA regulations requiring passengers to be seated while taxiing. And the list of things I’ve experienced by FA’s goes on, and I’m sure yours does also about passengers, so suffice it to say, this is really a human being problem, and not an airline, aviation, or commercial aviation problem. The state of human society is what’s really the issue, not passengers or FA’s.