Odd behaviour. One more reason to use the ToE forums.
That's not really a fair characterization.
There are basically two choices when allowing folks to register and post at a particular site. One method requires the registrant to wait to receive a confirmation email and then follow the links it contains to confirm the account before allowing someone to post. Sometimes this is even taken a step further to require an admin to approve a new member before they are allowed to post.
Bot spamming is indeed an issue that needs to be dealt with in some manner or other. It can be extremely annoying to wade through a bunch of posts with links to viagra ads and similar ilk.
While one can argue that one method may be marginally better than another the attempt to immediately allow someone to post and then have software checks in place to eliminate the spamming issue isn't an unreasonable choice. The fact that this screws up so infrequently is evidenced by the fact that it's difficult to remember what the issue was in the many months between occurances of this problem.