I'm job hunting at the moment so I can understand the compulsion to answer the phone even at inopportune times - I have this irrational fear that if I don't, they might not bother calling back and offer the job to someone who did answer (like it's a radio cash giveaway, first one to answer their phone and say the secret code word gets the job!) But I would never. ever talk to a potential employer that way.
I think this attitude is absolutely cross generational. When I worked in retail management I constantly had candidates of all ages snap at me for calling the home phone instead of the mobile and vice versa, or for daring to call when they were in the middle of something (like I knew exactly what they were doing and was just waiting for the worst time to call). Retail isn't the same as a corporate job, obviously, but this was at the height of the GFC and I was so surprised that candidates who wrote (very eloquently, in many cases) cover notes explaining how desperate they were for work would be so rude and dismissive.