I always loathed Foursquare because it interfered with social occassions. You and some buddies walk into a location, and suddenly everyone has to take out cell phones. It's relieving to hear that the company's strategy was always to become less obtrusive. I may actually download the new app now.
I've actually found it to be a social benefit myself. Most of the people I go out with use it and we tend to compete and discuss what picture and tagline we're going to use and who is better and who checks in first. Much of the time the conversation later goes on to what cool things our friends did lately or if we can tell it is snowing somewhere better through 4sq or Instagram, often with much showing of the phones…
I hardly speak for every obsolete senior citizen over the age of 25, but its more of a perception of what is good or bad taste rather than neo-amish-ness. Social etiquette. For any elderly geezer over the age of, perhaps, 30, walking into a social occasion and ignoring the meatspace people to instead play with a phone would be considered intentionally highly insulting. If gentlemanly behavior means always doing everything possible to increase the comfort of those around you, which is a reasonable short definition, ignoring people to play on the phone doesn't score very high.