Not surprising in the least. When I mention that I am a school teacher I often get given a negative view of the younger generations  - in particular about their rudeness, lack of respect, and laziness.  
The reason as to why many of the elderly do this is perhaps significantly more complex than simply gaining an assurance of self-worth by negating those who represent youthfulness with all its potent energy and beauty. Many are genuinely concerned that an erosion of their traditional values - cornerstones of their world - will steadily collapse the integrity and strength of our societies. It is quite understandable and usual that people will feel better when they have had a chance to express their concerns.