Good point. This is why an American President doesn't sit down for a face to face with a two-bit lunatic tinhorn dictator from some backwater country with nuclear aspirations (I'm look at you Kim Jon Il) to talk them out of it. When the person with power sits down with the lunatic it gives the lunatic credibility. The politically savvy will treat, if possible, the opponent with actual credibility and facts the same way: dismiss them, ignore them, and refuse to debate them these very grounds: "No one takes this laughing stock seriously, I'm not going to give them credibility by being seen with them." The very act of debating them raises them to your status. Makes them a choice.
There is another rule of social interaction:
The person with the greatest behavior flexibility controls the interaction - and the person who controls it appears to win every time.
This is seen daily at the super market as the cart approaches the checkout stand and the toddler sees the strategically placed candy bar...
"Momma, want dat."
"You just had a sweet baby"
"Momma. WANT dat!"
"I said, you just had a sweet baby."
"MOMMA. WANT DAT!"
"Not to day, sweet'ums"
Queue jet engines. Queue throwing self on floor. Queue screaming, thrashing, hitting mother....
Queue every head turning to stare at the Mother insisting she stop that disturbance without raising her hand or voice....
Queue momma reaching for candy bar and handing it to cashier.
Who was more powerful in size? Was right? Who won?
Now what is momma had had the behavioral flexibility to throw HERSELF on the floor and scream and thrash (without emotion - just doing the same behavior)? The monster is robbed of his one power. The power to humiliate and socially pressure.
This works. My friend has two daughters who are holy terrors. They have ear splitting screams and when they want something they employ them to get what they want. So if I was in a conversation with their dad and they started demanding something this way, I would join them, without emotion, raising my voice leaning forward and demanding that daddy give them what they want. Instant silence. Their eyes get as big as saucers, they sit back and you hear not another peep.
In short, the creationist and theists should be the one clamoring for debates with evolutionists and atheists and the response of the latter should be simple and straight forward: The creationist/theistic stance is patently delusional and we don't waste our time debating delusional people.
Let them whine and stop and complain. The more they do the more rational people see them for what they are.