For clarity I'm talking about large scale pitched battles where there could be thousands upon thousands of corpses at the end. After the victor was decided did the winning side (or losing side for that matter) ever bother to bury or collect the fallen?
This older answer might e of interest.
Greetings. Not to discourage further responses, but do check out these older answers :
How did Spartans treat the dead of their enemies? by u/Iphikrates
Hope this helps.