I find this pretty typical of AWS TBH. You could ask the similar questions about other service like: Why can I make IAM policies for EC2 that key in on tags,

I find this pretty typical of AWS TBH. You could ask the similar questions about other service like: Why can I make IAM policies for EC2 that key in on tags, but not other services? Why can I filter on tag for some resources in the console but not all? Why don't ALL resources support tags?! IAM would be way less of a PITA if you could put resources into groups.. Hey, if they had tag support for all of their resources and you could restrict access to them like ec2 that would be like resource groups... Why can't I pay more to just scale ELB's up? Why don't ELB's support connection draining...(this has been addressed but was the most complained about ELB shortcoming for a long time). Etc. Etc. Etc. But hey, things are not so bad and have really improved quite a bit in all fairness.