IMO they haven't for awhile IF they ever did. In the beginning if they showed any honor toward those who put themselves in harms way it was an act. And now since it doesn't benefit them for re-election purposes, they don't even bother putting on an act.
This is how the narcissistic mind works. They'll only do something (even distasteful in their mind) only if it furthers their agenda. In their mind, the veterans should be honoring them. It's beneath them to say "thanks" to anyone. They are royalty. I've read some articles concerning mental illness and how they should be removed under the 25th amendment.