"Thanking" ex-soldiers is not about showing gratitiude, it's about smug self-satisfaction and flag waving by those "thanking" them. If people really cared about them, they would be offering condolences for their lost innocence and their dead friends.
In May 2013, a series of pictures hit the news showing the faces of British soldiers - before they ever seeing combat, during, and after. You can see the lost hope, joy and innocence in their faces and especially their eyes.
Those who join "professional" armies usually do it for one of several reasons, though there are probably others:
- "tradition" or family and peer pressure
- believing propaganda, ignorance of actual motivations for war
- being driven by political or religious ideology
- nationalism under the false claim of "patriotism"
- a willingness to commit violence, racism
- gangs seeking military training
- financial desperation, lack of educational and other employement opportunities
The last is the only one where I can empathize with and be supportive of them.
They are not owed "thanks" when wars today are driven by corporate profits, religious ideology, nationalism, and theft of other nations' resources. They are at best owed condolences for the mistake of joining, and condemnation if they still believe that illegal invasions of other countries served any purpose other than increasing the profits of corporations.