I'm sorry that you find the expectation that when you claim something it needs to be true tiresome, but I'm afraid it does. What you could always do is stop writing things which are not true, then you wouldn't have to deal with "tiresome" requests for proof, would you.
You made an appalling allegation about Odds - an allegation which in real life has seen the person who made it sued for libel.
So yeah - you do have to prove it.
That you reacted to a polite request in the way you did says that you have no proof, that the allegation is a lie.
Seriously - try being honest and truthful for a change.