I do not think anyone check a profile whether they are banned or not when sending merits. There has no tag of banned user in the forum. I doubt a lot of people use personalized script to check status.
If anyone takes such time to check user status, if they are banned or not, if they are active or not, no one would distribute all of their merits.
On top of that, merit should be given to quality post so that readers can identify the quality posts when they visit a thread. So, after all, I should give priority to quality rather than all other aspects.