There was a discussion on the forum here - which suggested that the reason this happened was because Contributions should alway be loading fresh data.
The jury seemed to be out on whether that should be default behaviour for Member fields.
Our scenario is members join up, and use Contact Reference field to assign themselves to a club (and then we build a Relationship from that).
When the member renews we absolutely want this data loading.
My feeling is this should be core behaviour but would be good to canvass opinions on this.