Spectators are affected by tp command blocks.

I expected the command block to only affect players in gamemode 0,1,or 2

I am very sorry if this is not a bug but it seems spectators are affected by command blocks. The information in the command block I found this out is /tp @a[r=3] ~ ~ ~(i used different cords.) When a clock hits this command block teleports all players including spectators.

Steps to Reproduce:
1. Make a command block that says /tp @a[r=3] CORDS. HERE
2. Make a hopper clock with a hopper going through the hoppers
3. Have a comparator receive a pulse and have the pulse go through a repeater into the command block
4:Go into gamemode 3 and walk within a radius of 3 from the command block
5. Hopefully u noticed the command block senses spectators.