Calling people who are simply following SOPs, that they didn't write, is a tad harsh.
When fuel is so expensive it falls to all of us to help each other. If you can accept a higher level and free a level for someone below you, take it if it is practical. If you slow down on the STAR, announce it to help the following aircraft.
Don't, however, react with anger: maybe an explanation that your SOPs are different would suffice.