He signed his contract in September 16. I think he had already peaked at that point? (he was injured a lot in the following 2 seasons) To answer your point, if I believed I was only paid 50% of what my contemporaries earned at a similar firm, i would absolutely ask for a pay-rise. If I didn't get it I would leave. What I wouldn't do it broadcast it to the media (they wouldn't care anyway! ). Walker did the right thing - he left and has earned more. Rose could have done the same. He didn't and chose to moan about it. The other Spurs players you mention haven't moaned and I think that's why they haven't been criticised.
I have no issues with footballers earning money, fair play to them! As for a short career, it is, but players at the top level will earn more in a few months than someone who works for 40 years will. I think sometimes footballers at the very top lose a bit of grip with reality. There are somethings that are best kept private. I wouldn't complain about my salary to a homeless person because it would appear vulgar. Rose complaining that £65k isn't enough when the average salary in the UK is what, £26k is also vulgar. People don't want to hear it.