Is not honoring bounces-to violation of RFC?

[Chip]

I know this question is not specifically germane to Postfix but everyone 
on this list has extensive experience with bouncing policies.

If a receiver of campaign emails (that promotes itself as an email 
security service) sends bounces to "reply-to" rather than "bounces-to" 
as a policy despite bounces-to present in all campaign emails headers, 
would this be considered a violation of RFCs?