As I mentioned to Mary privately, yogurt with fish in it is very common (yoplait, for example) and vegetarians who know that kosher gelatin is made of fish don't eat it; this can result in the food options at the cookie table being, essentially, cookies, which are of course a terrible thing to eat if you will be needing to concentrate during the next session. Because of this I tend to consider the break food to be an attractive nuisance rather than a benefit. I don't know if it's even possible to get people at venues to be sensitive to these issues, but I certainly support the effort Mary is making to get them to try, and I think specificity is a good thing. I applaud your flexibility, but not everyone is in a position to be as flexible; in particular, given the number of graybeards who attend IETF, I think paying attention to the problem of excessive sugar in break foods is really important.